Conditionals

(условной) части.
Придаточная часть выражает условие и содержит слова:
If -

если
When - когда
Unless - если не

Главная часть показывает результат соблюдения условия придаточной части.

или будущему.
If Present Simple, Future Simple.
If I find a good

job, I will be happy.

(keep) polluting the environment. 2. If we dump all sorts of

chemicals into rivers, we _____ (not be able to) swim in them in the future. 3. If we ______ (not stop) cutting down so many trees, we ________ (endanger) our oxygen supply. 4. If the global temperature ________ (rise), sea levels _______ (rise) too. 5. People ________ (run out of) drinking water one day if they _______(not use) it more rationally. 6. If a human __________ (want) to help the planet, then he _____________ (have to) change his habits.

к настоящему или будущему.
If Past Simple, would+verb.
Note: в условной части

глагол to be может иметь форму were для любых подлежащих.
If I were you, I would read this fantasy book.

him to the party.
2- If I … (be) taller, I

… (become) a basketball player.
3- If an asteroid … (hit) our planet, it … (cause) an ice age.
4- John … (travel) around the world if he … (win) a lottery prize.
5- We … (go) to Spain this winter if we … (have) enough money.
6- She … (not mind) if you … (borrow) her car.