2 . A: Excuse me, do you know where the chemistry lab is?
B: Yes. It’s just on the fifth floor of this b    1    .
A: How often do you do c    2    experiments there?
B: Twice a week.
A: Can you go there without a t    3    ?
B: No. That’s not allowed.
A: What does the teacher often tell you to do when you are doing an e    4    ?
B: He often tells us to look c    5    and follow the i    6    .
A: What will you do when you finish the experiment?
B: We must put e    7    back in the cupboards and wash our hands.
A: Right. It is very i    8    to keep the lab clean.
B: Yes, safe as well. We must turn off the e    9    before l    10    the lab.

3 . 根据对话内容，从对话后的选项中选出能填入空白处的最佳选项，选项中有两项多余选项。
——Can you help me?
——Sure, what’s the problem?
——    1    .
——Well, how about San Francisco? We went there last year and had a great time.
——    2    
——Well, there is Golden Gate Bridge of course, and Golden Gate Park. It’s a really big park. You can go for long walks or take a rest in the Japanese Tea Garden. It’s beautiful there.
——    3    
——There is also a place called Fisherman’s Wharf. That’s really popular with tourists. There are lots of shops, cafes and restaurants. And from there you can go on a boat trip to Alcatraz. You know, it’s a small but very beautiful island.
——    4    
——No, you can’t stay on the island; there aren’t any hotels. You can only go for the day. I think I’ve still got a book about San Francisco. I can lend it to you.
——    5    
A. What can you do there?
B. Oh, great! What a great place to stay in!
C. What an idea! What is the best time to go there?
D. I can’t decide where to go for the holiday — any ideas?
E. Thanks a lot. San Francisco, here I come!
F. Hmm, that sounds good.
G. How can I go there?