First Conditional

Focus: Plans & Decisions · First Conditional · Modal Verbs · Unless · Zero vs First
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Vocabulary: Plans & Decisions

Note: These words and phrases appear naturally in First Conditional sentences — "If I decide to go, I will book in advance." Learn them as chunks, not just single words.

1. Making Plans

to plan (to do sth)/plæn/планирам
to decide (to do sth)/dɪˈsaɪd/решавам
to book / to reserve/bʊk/резервирам
to arrange (a meeting)/əˈreɪndʒ/уреждам, организирам
to cancel/ˈkæn.səl/отменям
to postpone / to put off/pəʊstˈpəʊn/отлагам
in advance/ɪn ədˈvɑːns/предварително
on time/ɒn taɪm/навреме

2. Making Decisions

to choose (between)/tʃuːz/избирам
to consider/kənˈsɪd.ər/обмислям
to make up one's mind/meɪk ʌp maɪnd/вземам решение
to agree (to do sth)/əˈɡriː/съгласявам се
to refuse (to do sth)/rɪˈfjuːz/отказвам
to change one's mind/tʃeɪndʒ maɪnd/сменям решението си

3. Outcomes & Consequences

to miss (a bus / deadline)/mɪs/изпускам, пропускам
to pass (an exam)/pɑːs/издържам (изпит)
to fail (an exam)/feɪl/провалям (изпит)
to succeed/səkˈsiːd/успявам
to regret (doing sth)/rɪˈɡret/съжалявам
consequence/ˈkɒn.sɪ.kwəns/последствие
opportunity/ˌɒp.əˈtjuː.nɪ.ti/възможност, шанс
risk/rɪsk/риск

4. Useful Phrases

What if…?/wɒt ɪf/Ами ако…?
I'll think about it./aɪl θɪŋk/Ще помисля.
It depends (on)…/ɪt dɪˈpendz/Зависи (от)…
as long as/æz lɒŋ æz/стига да, при условие че
provided (that)/prəˈvaɪ.dɪd/при условие че

Grammar Lab

Six sections. Read every explanation before the exercises. Each section builds on the last.
1

First Conditional — Core Rules

Real future possibility — something that might happen

We use the First Conditional for specific future situations that are realistically possible. Unlike the Zero Conditional (always true facts), the First Conditional is about something that might happen in the future. The if-clause uses Present Simple; the result clause uses will + base verb. Never use "will" directly after "if."

Structure

  • If + Present Simple → will + base verb
  • "If it rains tomorrow, I will stay at home."
  • "If she calls, I will answer."
  • "If you study, you will pass."
  • The if-clause can come second (no comma needed): "I'll call you if I have time."

The Most Important Rule

  • ⚠️ NEVER use "will" directly after "if"
  • ❌ "If it will rain, I will stay home."
  • ✅ "If it rains, I will stay home."
  • The if-clause is always Present Simple, even though the meaning is future.

Common Topics

  • Plans: "If I get the job, I will move to Sofia."
  • Warnings: "If you don't hurry, you will miss the bus."
  • Offers: "If you need help, I will call you."
  • Decisions: "If the price is good, I will book it."
📝 Exercise A — Easy: Choose the correct form to complete each First Conditional sentence.
1. If she ___ (call), I will answer.
2. If you study hard, you ___ (pass).
3. If the price ___ (be) good, I will book it.
4. I will call you if I ___ (have) time.
5. If he ___ (not / hurry), he will miss the bus.
🎯 Exercise B — Harder: Write the full First Conditional sentence using the words given.
1. If / it / rain / we / not / go out →
2. If / she / arrive / on time / we / start →
3. I / buy / the ticket / if / the price / be / good →
4. If / you / not / book / in advance / you / not / get / a seat →
2

Negative Forms

Negative condition (don't/doesn't) · Negative result (won't)

Either or both clauses can be negative. The negative of "will" in the result clause is won't (= will not). The negative in the if-clause uses the standard Present Simple negative: don't / doesn't. You can mix positives and negatives freely.

Negative If-Clause

  • don't / doesn't + base verb
  • "If she doesn't come, we will leave."
  • "If you don't book early, there won't be seats."
  • ⚠️ NOT: "If she won't come…" — no will in the if-clause

Negative Result

  • won't + base verb (= will not)
  • "If it rains, we won't go out."
  • "If you miss the train, you won't arrive on time."
  • "If she refuses, he won't ask again."

Both Negative

  • Both clauses can be negative at the same time
  • "If you don't study, you won't pass."
  • "If he doesn't decide, we won't book it."
  • "If she doesn't call, I won't know."
⚠️ Key difference from Zero Conditional: In Zero Conditional the negative result uses "don't/doesn't" (always true). In First Conditional the negative result uses won't (future). Compare: "If I don't sleep, I feel tired." (Zero) vs "If I don't sleep tonight, I won't feel well tomorrow." (First)
📝 Exercise A — Easy: Choose the correct negative form.
1. If she ___ (not / come), we will start without her.
2. If it rains, we ___ (not / go) to the park.
3. If you ___ (not / hurry), you will miss the bus.
4. If you don't book in advance, there ___ (not / be) any seats.
🎯 Exercise B — Harder: Write the negative form of the bracketed verb.
1. If you ___ (not / decide) soon, you will lose the opportunity.
2. If he misses the meeting, his boss ___ (not / be) happy.
3. If she ___ (not / study), she ___ (not / pass) the exam.
4. If they ___ (not / cancel) in advance, they ___ (not / get) a refund.
3

Modal Verbs in the Result Clause

can · must · might — alternatives to will

The result clause doesn't have to use "will." You can replace it with a modal verb to express a different shade of meaning. The if-clause always stays the same: Present Simple. Only the result clause changes.

Can — Ability / Permission

  • Meaning: you are able to / allowed to
  • "If you book early, you can choose your seat."
  • "If you pass the exam, you can join the course."
  • "If she agrees, we can start planning."

Must — Obligation / Rule

  • Meaning: it is necessary / required
  • "If you travel abroad, you must have a passport."
  • "If you join the course, you must attend every class."
  • "If you drive, you must stay sober."

Might — Possibility (Maybe)

  • Meaning: maybe — less certain than will
  • "If it's sunny, we might go to the park."
  • "If he calls, I might change my mind."
  • will = very likely · might = possible but not sure
💡 Quick guide: "If you pass, you can join" (permission) · "If you join, you must attend" (rule) · "If it rains, we might stay in" (uncertain) · "If you hurry, you will catch the train" (near certain)
📝 Exercise A — Easy: Choose the correct modal verb — will, can, must, or might.
1. If you have a ticket, you ___ enter the venue. (permission)
2. If you travel abroad, you ___ have a valid passport. (rule)
3. If it snows tonight, school ___ be closed tomorrow. (maybe)
4. If you hurry, you ___ catch the last train. (near certain)
5. If she passes, she ___ join the advanced group. (permission)
🎯 Exercise B — Harder: Rewrite each sentence using the modal shown.
1. [can] "If you book early, you are allowed to choose your seat." →
2. [must] "If you join the course, attendance at every class is required." →
3. [might] "If he cancels, perhaps we will postpone the trip." →
4. What modal: "If you need help, ___ I call someone?" (offering ability)
4

Questions & Short Answers

Will / Won't questions and how to answer them

To make a question in the First Conditional, invert the result clause: Will + subject + base verb? The if-clause stays exactly the same as in a statement. Short answers use will / won't — not "do/does" (that's Zero Conditional).

Question Structure

  • If-clause stays the same — Present Simple
  • Question part: Will + subject + base verb?
  • "If it rains, will you stay at home?"
  • "Will she come if we invite her?"
  • The question can come before or after the if-clause.

Short Answers

  • Yes, I will. / No, I won't.
  • Yes, she will. / No, she won't.
  • ⚠️ NOT "Yes, I do." — that is Zero Conditional.
  • "Will you come if I call?" — "Yes, I will."
  • "Will he decide today?" — "No, he won't."
💡 Contrast with Zero Conditional: Zero → "Does ice melt if you heat it?" — "Yes, it does." · First → "Will the ice melt if we leave it outside?" — "Yes, it will."
📝 Exercise A — Easy: Choose the correct short answer.
1. "Will you come if I call you?"
2. "Will she pass if she doesn't study?"
3. "Will they cancel if it rains?"
4. "Will you book if the price is good?"
🎯 Exercise B — Harder: Write Will or Won't to complete the question or short answer.
1. "___ she agree if we ask her nicely?"
2. "If you don't decide today, ___ you decide tomorrow?"
3. "Will he come if we invite him?" — "No, he ___."
4. "Will you miss the bus if you don't leave now?" — "Yes, I ___."
5

Unless

Unless = if … not — the negative condition in one word

Unless means the same as "if … not". It introduces a negative condition without needing to write "if … don't/doesn't." The verb after "unless" is always positive (Present Simple) — because "unless" is already negative. The result clause still uses will / won't exactly as in any First Conditional.

Structure & Examples

  • Unless + Present Simple → will / won't + base verb
  • "Unless you hurry, you will miss the bus."
    = "If you don't hurry, you will miss the bus."
  • "I won't go unless you come."
    = "I won't go if you don't come."
  • "Unless she calls, I won't know."
    = "If she doesn't call, I won't know."

The Golden Rule

  • ⚠️ After "unless" — always use a positive verb
  • ❌ "Unless you don't hurry…" — double negative, wrong
  • ✅ "Unless you hurry…" — correct
  • "Unless" already contains the "not" — adding another negative cancels it out and changes the meaning.
💡 Tip: When you see "unless," replace it mentally with "if … not" and the sentence should make the same sense. "Unless you book early, seats will sell out" = "If you don't book early, seats will sell out." If both versions make sense, you've used "unless" correctly.
📝 Exercise A — Easy: Rewrite each sentence using UNLESS. Type the full sentence.
1. "If you don't hurry, you will miss the train." →
2. "If she doesn't call, I won't know." →
3. "If you don't book early, seats will sell out." →
🎯 Exercise B — Harder: Complete with the correct Present Simple form of the verb after UNLESS.
1. Unless you ___ (decide) today, the offer will expire.
2. Unless she ___ (call) me back, I won't know the answer.
3. He won't succeed unless he ___ (work) harder.
4. Unless they ___ (cancel) in advance, they won't get a refund.
5. I won't change my mind unless you ___ (give) me a very good reason.
6

Zero vs First Conditional

Always-true facts vs real future possibilities

The biggest source of confusion at this level is choosing between Zero and First Conditional. The key question is: Is this always true (a fact, a law, a habit) — or is this something that might happen once in the future? If it's always true → Zero. If it's a future possibility → First.

TypeMeaningStructureExample
Zero Always true — fact, law, habit If + Present Simple → Present Simple "If you heat ice, it melts." (100% always)
First Specific future possibility If + Present Simple → will + base verb "If it's hot tomorrow, we will go to the beach."

Zero Conditional Signals

  • Result is certain every time — no exceptions
  • Could replace "if" with "when" or "whenever"
  • Scientific facts, natural laws, habits
  • "If you don't sleep, you feel tired." (always)

First Conditional Signals

  • Result is possible but not guaranteed
  • About a specific future moment or decision
  • Plans, warnings, offers, threats
  • "If she calls tonight, I will tell her." (specific)
⚠️ Same if-clause, different meaning: "If it rains, the ground gets wet." (Zero — always true) vs "If it rains tomorrow, we will cancel the trip." (First — specific future plan)
📝 Exercise A — Easy: Select Zero or First Conditional for each sentence.
1. "If you mix red and blue, you get purple."
2. "If she calls tonight, I will tell her."
3. "If you heat water to 100°C, it boils."
4. "If it snows tomorrow, we will cancel the trip."
5. "If plants don't get water, they die."
6. "If you don't book early, there won't be seats."
🎯 Exercise B — Harder: Fix the grammar mistake in each sentence. Type the corrected result clause only.
1. (First) "If I see him, I tell him the news." → result should be:
2. (Zero) "If water reaches 100°C, it will boil." → result should be:
3. (First) "If you will come to the party, it will be great." → if-clause should be:
4. (First — missing will) "If she doesn't call, I not know." → result should be:

Reading: First Conditional in Context

Read each text carefully, then choose the best answer. All four texts use the First Conditional — covering core rules, negatives, modals, unless, and Zero vs First.
🎓

Text 1: Lena's Big Decision

Lena is a student in Plovdiv who is thinking about her future. "If I pass all my exams this summer, I will apply to a university in Sofia," she tells her parents. "If I get a place, I will move there in September." Her mother is supportive: "If you work hard, you will succeed — I'm sure of it." Her father is more cautious: "If you decide to go, you must plan everything carefully. You'll need to find accommodation, and if you don't book in advance, all the good flats will already be taken." Lena nods. "I know. And if I don't get into my first choice, I won't give up — I'll apply again next year." She has already started revising. "Unless I pass, I can't go," she says quietly, "so I won't stop studying until the exams are over."

Questions:

1. What will Lena do if she passes her exams?

2. What does Lena's father say she must do if she decides to go?

3. "Unless I pass, I can't go." This means the same as:

4. What will Lena do if she doesn't get into her first choice?

✈️

Text 2: The Travel Plan

Stefan and his friend Ivo are planning a trip. "If we book the flights today, we will get a much better price," says Stefan. "If we wait, the tickets will cost twice as much." Ivo isn't sure. "If I don't get my holiday approved by Friday, I won't be able to go at all." Stefan is disappointed. "If you can't come, I might go alone — or I might just postpone it." Ivo thinks for a moment. "Will you be angry if I cancel at the last minute?" he asks. Stefan shakes his head. "No, I won't be angry — but I will be disappointed. Anyway, unless your boss refuses, you should be fine. Just ask him today." Ivo nods. "You're right. If I ask him now, he will probably say yes. And if we go, we must book the hotel in advance — otherwise we won't find a good one."

Questions:

1. What will happen to the ticket price if they wait?

2. What might Stefan do if Ivo can't come?

3. "Will you be angry if I cancel?" — Stefan replies: "No, I ___."

4. What must they do if they go on the trip?

🏫

Text 3: The Teacher's Rules

On the first day of term, Mrs Dimitrova explains the rules to her new class. "If you arrive late, you must wait outside until the break," she says firmly. "If you miss more than three classes, you won't be allowed to sit the final exam." She continues: "If you work hard and hand in all your assignments, you can take part in the school competition at the end of the year. If you win, the whole class will go on a trip to Varna." One student raises her hand. "Will we fail the year if we miss too many classes?" she asks. "Yes, you will," says Mrs Dimitrova. "But unless you have a very good reason, I expect everyone to be here. If you're ill, call the school — we will arrange for you to catch up."

Questions:

1. What must a student do if they arrive late?

2. What can students do if they work hard and hand in all assignments?

3. "Will we fail if we miss too many classes?" — "Yes, ___."

4. What will the school do if a student is ill?

🌤️

Text 4: Weekend Plans

Maya and her friends are making plans for the weekend. "If the weather is good on Saturday, we will go to the Rhodope Mountains," she says. "If it rains, we'll probably stay in and watch a film — but if it's only cloudy, we might still go." Her friend Kristina asks: "Will you drive if Georgi can't come? He has the car." "If Georgi can't come, we won't have a car," says Maya, "so we'll take the bus unless someone else can drive. If we go by bus, we must book tickets in advance — buses to the mountains fill up fast at the weekend." Kristina thinks for a moment. "You know, if you always wait for perfect weather, you'll never go anywhere," she laughs. Maya agrees. "You're right. If it doesn't rain heavily, we'll go — it always looks nicer when the hills are misty anyway."

Questions:

1. Where will they go if the weather is good on Saturday?

2. What will happen if Georgi can't come?

3. If they go by bus, what must they do?

4. What does Kristina say will happen if Maya always waits for perfect weather?

Text 1 / 4

Cloze Text: The Job Interview

Choose the correct word or phrase. The text tests all 6 parts of the First Conditional from Grammar Lab: core rules, negatives, modal verbs, questions & short answers, unless, and Zero vs First.

The Job Interview

Dimitar has an important job interview next week. "If I (1) this job, my whole life (2) ," he tells his flatmate. "The company is based in Sofia, so if I (3) the offer, I must find a new flat within the month."

His flatmate Ana gives him advice. "If you (4) well, you (5) them," she says. "But if you research the company first, you (6) answer their questions much more confidently." She adds: "If they ask about your salary, you (7) give them a clear number — don't be vague."

Dimitar asks: " (8) it be a problem if I'm a few minutes late?" Ana shakes her head. "No, it (9) — if you call ahead. But (10) you warn them, they (11) be impressed."

Finally, Dimitar thinks about the difference between his current job and this one. "In my current job, if I arrive early, I always (12) the best desk by the window. But for this interview, if I arrive early on the day, I (13) a great first impression — this is a one-off situation, not a daily habit." He smiles. "Unless something goes badly wrong, I think I (14) actually get this job."

Exercises (15 Sets)

All 15 sets practise the First Conditional only — matching the 6 parts of Grammar Lab: core rules, negatives, modal verbs, questions & short answers, unless, and Zero vs First.

Tense Writing Practice

Five exercises, 10 sentences each — all mixed tenses.
Put the verb in brackets into the correct tense.

Gerund or Infinitive?

Five mixed exercises. The verb before the gap decides the form.
Key verbs with gerund: enjoy · finish · like · love · hate · avoid · mind · stop · practise · keep · suggest · consider
Key verbs with infinitive: want · need · decide · hope · plan · manage · promise · agree · refuse · expect · offer · learn · forget · remember

Key Word Transformation

How it works: You are given a sentence and a key word. Rewrite the sentence so it means the same, using the key word. The beginning is given — you write the rest. Punctuation counts.
⚠️ Do not change the key word. Check spelling and punctuation before clicking Check.