单句改错We persuaded him to stay at home,but he didn'tShe insisted in writing a letter to her husband at once.Heinsisted that he hear someone in the next room全部是有错误的，另外insisted 这个句子省略了should 所以hear 用原形是对的

We persuaded him to stay at home,but he didn't（没有错误）
She insisted on writing a letter to her husband at once.（in改为on）
He insisted that he hear someone talking in the next room （hear sb doing sth）

She insisted in writing a letter to her husband at once.
Heinsisted that he HEARD someone in the next room

2楼的完全是放P
第一句We persuaded him to stay at home,but he didn't没错
第二局She insisted in writing a letter to her husband at once.
in 改成 on 坚持做某事是 insist on doing sth
第三题 也没错 因为 insist that 后面动词用原型 句型是虚拟语气!
insist that sb should do sth.should可省略