People are _________the use of alternative energy sources. Because the fossil fuels _________will be used sooner or later.

The workers are all tired, but ________ of them stopped ________ a rest.

So far we have done a lot to build a low-carbon economy, but it is ____ ideal (理想) We have to work still harder

vernment is aiming to reduce the unemployment,but it’s quite _______ to have a job at all these days.

________ some teenagers don’t realize is ________ difficult life can be after they get addicted to drugs