That was only a guess of mine.

那只不过是我的猜测。

Can you guess this riddle?

你能猜出这个谜语吗？

Not knowing which way to go, I had to guess.

不知道该走哪条路，我只好猜一猜。

I guess what you were really trying to say is that you've got nothing to do these days.

我想你真正要表达的是你这几天无所事事。

— Are you ready to go?

你准备好出发了吗？

— I guess so / not.

我想是的/没有。