_______is known to us all is that the 2016 Olympic Games will take place in Rio de Janeiro.
| A．What | B．which | C．As | D．It |
For most Americans, their 18th birthday the end of one part of their life and beginning of another．
| A．predicts | B．tells | C．marks | D．signs |
It ______ heavily when he got back home for he was wet all over．
| A．was raining | B．must have been raining |
| C．must be raining | D．rained |
—Very little use was _____ the waste water in the past．
| A．made of | B．make from | C．made up | D．make into |
—Miss Broun is very busy, isn’t she?
—So she is．She has greater responsibilities since she was promoted．
| A．taken off | B．taken after | C．taken in | D．taken on |
—You can’t imagine ____ fantastic fun web chatting is．
—Really? But it may cause a lot of trouble sometimes．
| A．what | B．how | C．why | D．so |