引导宾语从句的that在下列情况下一般不省略：

1. 宾语从句前有插入语。如：

We hope, on the contrary, that he will stay at home with us. 恰恰相反，我们希望他和我们呆在家里。

2. 有间接宾语时。如：

He told me that he was leaving for Japan. 他告诉我他要去日本。

3. that在与之并列的另一个宾语从句之后。如：

He said (that) the book was very interesting and that(不省略) all the children like to read it.他说那本书很有趣，所有小孩都喜欢读。