Why are you standing here, Tom—I can’t see the blackboard clearly. Two tall boys aresitting ____ me.

(2014·河北保定模拟)The authorities will________the case further before they can come to a conclusion about it.

.People have planted a great many trees in order to _____ wind and sand in the desert.

We invited her to dinner but she didn’t even bother to _______.

Finally, I bought the new book,_____I spent twenty yuan, in the bookstore where a friend of mine is the boss