谁能告诉我you can spend time to exercise怎么错了？怎么改正？

spend time on sth
固定搭配 把to改成on

you can spend time exercising
sb. spend some time doing sth. 固定搭配，某人花费时间做某事

you can spend time on exercise

spend用法:
spend + on + n.
或者spend + doing sth.

sb. spend some time (in)doing sth.
还有一个是用sb. spend some time on n
改为you can spend time exercising 或
you can spend time on exercise