The man we followed suddenly stopped ad looked as if________ whether he was going I the right direction.

For holidays, many people visit the Great Barrier Reef _____ the northeast coast of Australia, which has 700 islands

Where did you get to know her?— It was in Harbin No. 3 High School ______ we studied.

What action should they _______ such a thing happening again

I think it takes a lot of practice to play the violin well.— . Practice makes perfect.