— Mum, I’m really about the result of the exam.— Cheer up. I believe you can be successful.
_____ the environment is important for human beings.
I can’t stand _____ for you so long.
—Is the bag beautiful? —Yes, at _____ it’s _____ the one you bought for me.
Our teacher told us that light _____ much faster than sound.
In our class _____ of the students _____boys.