求解英语选择题 高手进!

题目

求解英语选择题 高手进!
（ ）Although it was very late when John began doing the job,he managed with his friend's assistance,___before the building was locked.
A.to be finished B.being finished C.finishing D.to finish
为什么选D?整句话的意思?可不可以将第二个逗号去掉?
（ ）I have tried ____worrying about it.?
A.to stop consciously B.to consciously stop
C.to conscious stopping D.to stopping consciously
选B为什么不选A?副词放置有规律可循吗?还是只是根据句意的通顺程度来选择的?

答案

D
可以
一般情况下,副词修饰动词,放在动词的后面.
to stop consciously worrying about it
分析这个时候,请问consciously是修饰stop,还是worrying.
为了明确对象,副词在前