How would you say "I think so" or "I guess" in Japanese?

Question

Answer

I would say "I think so" in polite way, そう思います sou omoi masu / そうだと思います sou dato omoi masu or just そうだと思う sou dato omou.

"I guess (so)" politely say - そうだと思います sou dato omoi masu or informally say, 多分 tabun :maybe.

I hope it helps you.

Answer

思います

私もそう思います　I think so too.

XXXXXX と　思います (I think)

XXXXXX と　思っています (I have been thinking)