YOU SAID:

I read that book in 2 hours.

INTO JAPANESE

私は2時間でその本を読んだ。

BACK INTO ENGLISH

I have read the book in two hours.

INTO JAPANESE

私は2時間で本を読んだ。

BACK INTO ENGLISH

I read a book in two hours.

INTO JAPANESE

私は2時間で本を読む。

BACK INTO ENGLISH

I read books in two hours.

INTO JAPANESE

私は2時間で本を読む。

BACK INTO ENGLISH

I read books in two hours.