为避免医生以，及病人对实验效应观察的主观偏性，可采用的方法是A.随机化B.单盲

A.do

B.are

C.does

A．She needs a new raincoat or umbrella.

B．It will probably rain tomorrow.

C．She doesn't know what the weather will be like tomorrow.

D．She doesn't know where the man put his raincoat or umbrella.

The man doesn't know where Candy is.

A．True.

B．False.

She is so ______ that she doesn't even know where Beijing is.

A．foolish

B．competent

C．innocent

D．ignorant

A．He doesn't know if Mr. Lee was born in Indonesia.

B．He doesn't know where Mr. Lee lived before.

C．He doesn't know when Mr. Lee would go to Hong Kong.

D．He doesn't know where Mr. Lee grew up.

The student says that ______.

A．he doesn't know anyone on his course.

B．he doesn't know the overseas students on his course.

C．there are no people from his country on his course.

D．there are few overseas students on his course.

John doesn't believe in ______ medicine; he has some remedies of his own.

A．standard

B．regular

C．routine

D．conventional

Not that John doesn't want to help you, _____ it's beyond his power.

(A) but that (B) for that (C) and that (D) in that

Not that John doesn't want to help you, _____ it's beyond his power.

(A) but that (B) for that (C) and that (D) in that