_______ is known to us is that time is limited and precious.
| A．What | B．That | C．It | D．As |
Our chemistry teacher announced that he would do the experiment in a different way
we might find interesting.
| A．which | B．in which | C．in that | D．whom |
While she is a lovely girl, she be extremely difficult to work with.
| A．may | B．must | C．should | D．can |
A dictionary is necessary if you want to learn English, so you’d 
better buy .
| A．this | B．that | C．it | D．one |
–Jimmy had a lot of parties recently.
—Yes, that might why he didn’t do well in the test.
| A．sum up | B．add up to | C．account for | D．make sense of |
—I’m afraid these flowers won’t be able to live through the winter.
—But I think otherwise. You see, measures _______ to take good care of them.
| A．have taken | B．had been taken | C．will take | D．are being taken |