he asked his mother that whether she knew what was going on then的错误是

问题描述:

he asked his mother that whether she knew what was going on then的错误是

不用中间的that
he asked his mother whether she knew what was going on then

多一个that改成:He asked his mother whether she knew what was going on then.whether she knew what was going on then是个宾语从句,作谓语动词ask的宾语(直接宾语,表示问话内容),whether本身可以引导宾语从句...