. According to some doctors, one of the ways to prevent us from growing old is to make sure
that our brains get enough___.
| A．performance | B．exercise | C．experience | D．sport |
Unless ________ to answer questions, the pupils won't talk in Mrs Smith's class.
| A．asking | B．asked |
| C．being asked | D．having asked |
—Where did you pick up the stamp?
—It was at the post office ________ we worked in the summer vacation.
| A．that | B．where |
| C．which | D．when |
Who ________ that played a trick on the new English teacher?
| A．it was | B．was it |
| C．he was | D．was him |
Where do you think ________ we can buy that bestseller?
| A．it is that | B．is it that |
| C．that | D．it |
There is no doubt that eating organic food will make you healthier, ________？
| A．will it | B．does it |
| C．is there | D．is it |