These days everybody is aware ................ the danger of smoking.

Are you still upset .................. what I said to you yesterday?

We're short ............... staff in our office at the moment. There aren't enough people to do the work that has to be done.

Scientists and engineers have invented filters and other methods of removing ................. from industrial wastes.

I'm sorry .................... the smell in this room. It's just been painted.

She's quite nice but I wouldn't like to be married ................ her.

We are always proud .............. our country.

I felt sorry ................. the children when they went ............... holiday. It rained every day and they had to spend most of the time indoor.

It wasn't polite .................. him to leave without saying a word.

Two things are very alike, so you say they are the .................. each other.