If-clauses; Modal verbs; Phrasal verb: look

If we ........ polluting, we will save the environment.

• stop

• don't stop

• stops

• will stop

If we don't protect endangered animals, they .........

• will survive

• survive

• won't survive

• do survive

When I ........ home from school, I usually rest for a while.

• will come

• won't come

• come

• comes

Unless we fight for our planet, we .........

• suffer

• suffers

• don't suffer

• will suffer

He won't help us if we ........ him.

• won't ask

• don't ask

• will ask

• asks

When the temperature is below 0º, water .........

• freezes

• will freeze

• doesn't freeze

• won't freeze

Unless you ........, you will regret it.

• will help

• help

• don't help

• won't help

........ we recycle, we will waste the planet's resources!

• If

• When

• Unless

• After

When I was on holiday I ........ sleep until late.

• could

• can

• must

Excuse me, ........you tell me where the post office is?

• must

• could

• mustn't