be running for exercise 还是 running for exercise
问题描述：
be running for exercise 还是 running for exercise
could be running for exercise
原文是这样但要写词组，奔跑锻炼身体
答
Be running for exercise
因为Could是Can的过去式,所以后面的be动词改为原形be.
如果用在句中就是She is running for exercise .要把be带到句子中的.
所以是个词组的话要带上be,不然放句子里不通顺.