Only after ______ made hundreds of experiments ______ succeed in solving the problem.
A. they had; did they
B. had they; they did
C. they had; they did
D. had they; did they
稽留热见于
A. 流行性脑脊髓膜炎
B. 败血症
C. 疟疾
D. 布鲁菌病
E. 霍奇金病
弛张热见于
A. 流行性脑脊髓膜炎
B. 败血症
C. 疟疾
D. 布鲁菌病
E. 霍奇金病
Half of the fruit ______ bad.
A. are
B. has
C. is
D. have