“我希望你忘了他”英文是I hope you can forgot him还是I hope that you can forget him……顺便给我解释一下为什么,

都可以，口语化一点就是第一句，正规一点就是第二句。

第一个句子语法错误了,应该为I hope you can forget him.其实,两个句子"I hope you can forget him." "I hope that you can forget him."都是正确的.不过,以formal的来说,应该取后者"I hope that you can forget him...