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【单选题】
火区启封必须具备下列条件：(一)火区内的空气温度下降到30℃以下，或与火灾发生前该区的日常空气温度相同。(二)火区内空气中的氧气浓度下降到5%以下。(三)火区内空气中不含有乙烯、乙炔，一氧化碳浓度在封闭期间内逐渐下降，并稳定在0.001%以下。(四)火区的出水温度低于25℃，或与火灾发生前该区的日常出水温度相同。(五)上述4项指标持续稳定的时间在()以上。A.
3个月
B.
6个月
C.
1个月
D.
1年
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举一反三
【单选题】Helen, do you want to go to _______ with me tonight?
A.
cinema
B.
the cinema
C.
see film
【单选题】—How tired I am! I can’t climb any further, Mom. —_________, Helen. You can do it!
A.
No problem
B.
That’s OK
C.
Come on
D.
Well done
【单选题】听力原文：Helen, do you know the manager's phone number? (3)
A.
No one is at home.
B.
You have got a wrong number.
C.
I have no phone at all.
D.
Sorry, I don't remember.
【单选题】( ) —Helen, do you know if Martin ________ to my party next week?
A.
think he will come if he ________ free.
B.
will come; will be
C.
will come; is
D.
come; is
E.
comes; will be
【单选题】— How are you, Mary? —___Helen.
A.
How are you?
B.
I’m fine. Thank you
C.
How do you do?
D.
Nice to see you
【单选题】—Helen, do you like math? —No, I don’t. It’s __________.
A.
interesting
B.
exciting
C.
difficult
D.
good
【单选题】听力原文：M: We've got three women researchers in our group: Mary, Betty and Helen. Do you know them? W: Sure. Mary is active and sociable. Betty is the most talkative woman I've ever met. But guess what? ...
A.
Helen is quiet.
B.
Helen is talkative.
C.
Helen is sociable.
D.
Helen is active.
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