Generally speaking,_____according to the directions,the drug has no side effect.a.when taking.b.when taken.
c.when to taked.when to be taken答：B译：一般说来，如果按说明书服用的话，这药是没有副作用的。析：when taken...= when it is taken ...=when the drug is taken ....
本题考查状语从句的省略，当状语从句中的主语与主句主语相同(或为it) ,且谓语中有be动词时，可以省略"主+be"。
也...
B可以认为是考查省略。当从句跟主句的主语是一致的时候，可以把从句的主语省略，如果从句的谓语有be动词的话，也一并省略。还原generally speaking, when the drug is taken according to the directions,the drug has no side effect. 省略主语the drug 和is ...
