96-05-34 96-05-38 两题请教

ecsniffer

34、The discovery of the antibiotic penicillin in 1928 has not produced antibiotics useful for the treatment of infectious diseases until 1940.
答案为has not produced错
but why?
38、Ozone is an unstable,faintly bluish gas that is the most chemical active form of oxygen.
答案为chemical错，but why?
thks....

真老九

34..用过去完成时


38。chemical>>>chemically，修饰active,化学活性的意思

xizzhu

以下是引用ecsniffer在2004-4-1 17:55:00的发言：
34、The discovery of the antibiotic penicillin in 1928 did not produce antibiotics useful for the treatment of infectious diseases until 1940.



答案为has not produced错


but why? ===> because of "in 1928", thus, 用过去时.


38、Ozone is an unstable,faintly bluish gas that is the most chemically active form of oxygen.


答案为chemical错，but why?===> the most +    chemically/adv. + active/adj.


thks....