---I haven’t seen my grandparents for long. I’m too busy ___ them these days.---Why not call them instead?
I’d like to have a word _____________ Tony. A. on B. with C. in
_____ 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.