To exercise twice every week is best.(改为同义句)------ ------ ------ ------ exercise twice every week.

问题描述:

To exercise twice every week is best.(改为同义句)
------ ------ ------ ------ exercise twice every week.

改为 It's the best to exercise twice a week.
To do sth. is+形容词
=It's 形容词 to do sth.

It is best to ...

It is best to exercise twice a week.