7.We'll never give in (whatever )they may do or say.

7.We'll never give in (whatever )they may do or say.
可以填no matter what
8.Dr.Smith is aware that we still have a long way to go in improving human living conditions and in fighting sickness(wherever it is found)
wherever 是无论在哪里,where讲不通
9.You should leave the cage immediately(lest)you wish to be killed by the bear.
可以用unless,wish是原形,当然可以,也可是should+动原
10.Substances will expend or contrat(when)heated or cooled,but this is not the case with water.
as being也可以
11.(Watch)a baby between six and nine months old,and you will observe the basic concept of geometry being learned.
不填Watching,因为前面是祈使句,用原形
12.Doctor says that no matter (waht)forceful arguments against smoking there are many people persist in smoking.
how+形容词,what+名词.arguments名词,forceful 是修饰arguments的
forceful arguments 是名词词组

7这是一句名词性从句。whoever，whatever，whichever引导让步状语从句时相当于no matter who/what/which,但是，no matter who/what/which不能引导名次性从句。但在状语从句中是可以互换的。
8 此类选项只能根据句子的意思判断，这里强调了任何地方，所以用wherever，并且，这里就可以用no matter where 替换了