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【简答题】
β-内酰胺类抗生素是一类化学结构中含有________环的抗生素,包括________类、________类和________类。
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皮皮学刷刷变学霸
举一反三
【单选题】— I am terribly sorry, sir. I thought it was a parking place. — _____. Here is your ticket. [ ]
A.
It doesn't matter
B.
You are right
C.
I can't agree with you
D.
Sorry, that's no excuse
【单选题】— _______, sir. — OK. I'll speak a little more slowly. [ ]
A.
Sorry, I don't see you
B.
Sorry, I can't follow you
C.
You can't speak so quickly
D.
Can I help you
【单选题】---Can I pay the bill by check? --- Sorry, sir. But it is our rule that payment ________be made in case
A.
can
B.
need
C.
shall
D.
will
【单选题】— Can I pay the bill by check? — Sorry, sir. But it is the management rule of our hotel that payment ________ be made in cash. [ ]
A.
shall
B.
need
C.
will
D.
can
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