--- I wonder how much you charge for your service.
--- The first two are free ______ the third costs $30.

At school, some students are active ______ some are shy, yet they can be good friends with one another.

One’s life has value _______ one brings value to the life of others.

Many of them turned a deaf ear to his advice ______ they knew it to be valuable.

—Why are you staring at me?
—You look stupid! The way you wear is ______ annoys me most.

________ I can’t understand is ________ he wants to change his mind.

—I still haven’t decided whether to go or not.
—But your time is running out. Please make up your mind ______ it is too late.

I don’t doubt_______what he said is true.

The woman was about to open the door _______ she heard a strange sound from inside.

You may use the room as you like ________ you clean it up afterwards.