我无话可说英语怎么说 不要太直白那种

I am speechless.
I have nothing to say.
There is nothing I can say.
I don't know what else to say.

No comments! 口语中常用,省略掉了I am,
意思是无话可说,无可奉告,没有疑意等都可以.

I don't know how to put it.

楼主意思是要使用比较隐晦的用语，不知我理解正确以否？
如果是，那答案应该是：
There is nothing I could do.
It might be hard to tell.
Cat got my tongue.

I have nothing to say.

It's really difficult for me to answer.