28. This morning Ms. Green entered our classroom, and _____ us something important about the coming exam, left.
| A．having told | B．told | C．telling | D．to tell |
12.So absorbed__________in her work that she didn't realize I was behind her.
| A．did she | B．was she | C．she did | D．she was |
11.It will take us another five years______the construction of all the 121 roads is completed.
| A．when | B．since | C．before | D．After |
9.Loulan City is not at all__________a traveler who has never seen the desert before can expect.
| A．that | B．what | C．which | D．Where |
8. The doctor insisted she____in bed. But her smiling face suggested there____nothing serious.
| A．stay; was | B．stayed; was | C．would stay; be | D．stay; be |
7.____________of the truth of the reports, he told his colleagues about it.
| A．Convincing | B．Convinced | C．To convince | D．Having convinced |