It’s only six o’clock now; Little Tom should be up ,though, because he _____ for nine hours.
| A．has been sleeping | B．had been sleeping | C．has slept | D．had slept |
----How unhappy your roommate looks!
----Yes，but he’s not willing to tell me what it is____ is troubling him.
| A．what | B．which | C．as | D．that |
It was along the Mississippi River _______ Mark Twain spent much of his childhood.
| A．how | B．which | C．that | D．where |
It was not until midnight __ they reached the camp site.
| A．that | B．when | C．while | D．as |
It was in New Zealand ___ Elizabeth first met Mr. Smith.
| A．that | B．how | C．which | D．when |
----Where did you get to know her?
------It was on the farm ____we worked.
| A．that | B．there | C．which | D．where |