"Many elderly people like going to parks and doing exercises."

Translation: 很多老人喜欢去公园做运动。

[RobertEddy]

We also like to stay home and work on Duolingo!

[Tim728458]

Is the "zuo" really necessary for this to be correct grammatically?

[KX3.]

It sounds unnatural, or is at least not idiomatic, without it.

[james189798]

我同意

[Alberto994251]

Yesterday, my Chinese teacher corrected my writing and said I should never say "比较老的女人". Apparently, it sounds very offensive, so is it OK to say "老人"?

[KX3.]

Yes, you shouldn't ever call a woman old! But yes, you can say 老太太 or 夫人 as a sign of respect for people older than you.