About _______ gene-targeting drugs are already in testing pipeline. It won’t be long ______ they are put into effect.
#14337
A
two dozen; before
B
two dozens; that
C
two dozens of; before
D
dozens; that
推荐题目
 In ____, he began to learn Russian, when he was in ______. 
#12067
A
1970; the 50’s
B
the 1970; his 50s
C
the 1970s; his fifties
D
1970s; his fifties
 This English book __________ five parts, __________ grammar.
#12225
A
includes; including
B
contains; including
C
includes; containing
D
contains; containing