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【单选题】
下列几种说法中，不能正确叙述β-内酰胺类抗生素的结构及其性质（ ）。A.
青霉噻唑基是青霉素类过敏原的主要决定簇
B.
青霉素类、头孢菌素类的酰胺侧链对抗菌活性甚为重要，影响抗菌谱和作用强度及特点
C.
在青霉素类化合物的6a位引入甲氧基对某些菌产生的β-内酰胺酶有高度稳定性
D.
青霉素遇酸分子重排，加热后生成青霉醛和D-青霉胺
E.
β-内酰胺酶抑制剂，通过抑制β-内酰胺酶而与β-内酰胺类抗生素产生协同作用，其本身不具有抗菌活性
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【单选题】According to the author, politicians in 'the age of ascendancy' thought that television interviewers_____.
A.
were their rivals in politics
B.
should be honored to meet them
C.
really aspired to be politicians too
D.
gave them difficult time in interviews
【简答题】A．preachers B．scholars C．custodians D．politicians
【单选题】Computers are very versatile. This sentence means ______.
A.
computers are very expensive
B.
computers can do many things
C.
computers are very good to play with
D.
computers are very cheap
【简答题】invar
【单选题】Personal computers are no longer something beyond the ordinary people they are available these days.
A.
promptly
B.
instantly
C.
readily
D.
quickly
【简答题】US politicians invariably b_______ trade as the enemy of the middle class, the major source of pressure on jobs and wages.
【多选题】根据《法律适用法》，我国法院在依法应适用外国法律时，如果该外国的不同地区实施不同的法律，应如何确定准据法？
A.
不能直接依据该国的区际冲突规则确定准据法
B.
可以直接选择适用该国任一地区的实体法
C.
适用与该涉外民事关系有最密切联系区域的法律
D.
依当事人的住所地确定准据法
【简答题】短文改错。 Some things about computers are easier as you may fear. First, computers are logical. Things at first seems difficult will make sense to you after you learn the rules. Second, it is really not h...
【简答题】Mobile phones are more accessible to people than computers are.
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