That 引导的宾语从句如：he suggests that the park is very popular.Lingling thinks the park will be busy .I dont think they allow people to swim in the lake .放在动词后面作宾语的句子，叫宾语从句。分三类，一类是that 引导的宾语从句，二是whether(无论)/if 如果，引导的宾语从句。还有就是连接代词，连接副词引导的宾语从句。（1）that 引导宾语从句，that 没有实际意义，通常可以省略。但不一定所有的动词可以接that 宾语从句。常用的有：suggest think believe expect feel hear hope preferPromise report say see tell understand warn(警告) （2）有时that 是不能省略 宾语从句主语是that,如：he says that that is a useful
