如果你想保持健康体魄，定期锻炼是必不可少的。

Regular exercise is essential if you want to ___keep ___in ___shape.

他每周去三次健身房以保持身体健康。

He goes to the gym three times a week to ___keep ___in ___shape.

游泳是夏季保持身材的好方法。

Swimming is a great way to ___keep ___in ___shape during the summer.