take exercise要加s吗

不加，take exercise 做体操，做健身活动；锻炼exercise作为 【体育锻炼】解释是为不可数名词。

如Take exercise in the open air. 在户外做运动.

exercise 作为【练习;习题】解释时， 为可数名词。

例句Try working through the opening exercises in this chapter. 做一做本章节的\'开篇习题。

He took up piano lessons, combining standard classical exercises with his own attempts at Gershwin. 他上钢琴课，一边进行标准的经典作品的练习，一边自己尝试练习格什温的作品。