zero conditional

If people ................ eat, they get hungry.

• do

• don't

• does

• doesn't

Water ........... if you boil it.

• evaporates

• will evaporate

• evaporate

• to be evaporated

If you ________ yellow and blue, you ________ green.

• get - mix

• mix - get

• mixes - gets

• get - mixes

If people _________ (not eat) they ________ (die).

• die

• dies

• do not eat

• did not eaten

When you _________ (fly) budget airline, you ________ (have) to pay for your drinks and snacks.

• flies

• fly

• have

• had

If you press that switch, the light (a)   on.

We refer to ______________ (time reference).

• Present

• Past

• Present, Past, Future

•  

  Future

If you __________, you_______ old early.

• get - smoke

• smokes - gets

• smoke - get

• get - smokes

If I ______, I _______ a headhache.

• cry - have

• have - cry

• has - cries

• cries - have

If it ________, the grass _________ wet.

• get - rain

• rains - gets

• rains - get

• grass - gets