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【单选题】
计划免疫分为主动免疫和被动免疫，( )。A.
主动免疫免疫效果维持时间长,被动免疫抗病力维持时间则短
B.
主动免疫免疫效果维持时间长,被动免疫抗病力维持时间也长
C.
主动免疫免疫效果维持时间短,被动免疫抗病力维持时间也短
D.
主动免疫免疫效果维持时间短,被动免疫抗病力维持时间则长
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举一反三
【单选题】The patient was cured by
A.
writing a letter.
B.
enclosing a cheque.
C.
mailing a letter.
D.
asking his brother to forgive him.
【单选题】A common goal is one in which
A.
all parties share the result equally
B.
the parties work toward a common end but benefit differently
C.
all parties work together to achieve some output that will be shared
D.
individuals with different personal goals agree to combine them in a collective effort.
E.
All of the above are characteristics of a common goal.
【简答题】失业保障是从那两个方面影响自然失业率?分别解释一下这两个方面是如何影响失业率的。
【简答题】当发动机运转时,能保持活塞的行程、气门的开闭、点火的顺序,时刻“同步”的装置是()
【简答题】Write a letter of application to the Department of Physics, University of Wisconsin, asking for admission as a graduate student. Your letter should contain the following points: 1. the reason why you ...
【简答题】He is tall and he has _____________ [braʊn]hair.
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