1道英语选择题.

选A.went on doing
首先，要区分go on doing sth.和go on to do sth.
go on doing sth.表示“继续做同一件事”
go on to do sth.表示“继续做另一件事”
根据意思理解，“经过短暂休息，他又继续做那份艰苦的工作。”显然，他在休息之前做的也是这份工作，休息之后继续做同一件事用"went on doing "的结构。

A

go on doing,继续做原来做的事
go on to do，继续做原来没在做的事

这里有了个again，显然他继续的是之前在做的事，所以选A

A
因为句中有again ， 表示动作在之前已在进行中，
故选went on doing

A.went on doing
词组来的，go on doing sth.继续做某事

二楼和ls都是好老师阿。记得我的英语老师也是这样教的。。好怀念阿。。恩。 这就是两种的区别to do 和 doing.
我举例吧：
It rained yesterday when I was doing my coursework at home. After answering a call from Mary, I went on doing the coursework again. An hour later Peter came over. After having a short talk with him I went on to cook.

二楼说的对