The police _________ the mountain to ________ the murderer.
A. is searching; search for
B. are searching for; search
C. is searching for; search
D. are searching; search for
He told me that he had mailed part of the samples样本 and that the rest _____ in a few days.
A. were following B. have followed
C. has followed D. was following
He will give us a report on how to study English well, but when and where ________.
A. is still unknown. B. hasn’t decided
C. is known D. haven’t been decided
We should work together to build a society for kids, ________free from war and violence.
A.one B.this C.it D.that
He slipped(溜进) into the classroom without ___________.
A. noticed B. noticing
C. being noticed D. was noticed
This special strain of rice makes _________ possible to produce one third more of the crop in the same fields.
A. it B. them C. which D. that
