Reading in dim light is hard on your eyes. [=it puts a strain on your eyes; it is not good for them]在昏暗的光线下读书对视力有害。

This kind of work can be hard on your back.这种工作会损伤背部。

These past few months have been hard on everyone, but things should get better soon.过去的数月对每个人来说压力都很大，但一切应该很快就会好起来。

Don't be too hard on the boy. [=don't judge or treat the boy too harshly]不要对这个男孩太严厉。

She is sometimes too hard on herself.她有时过于苛待自己。

There's no need to be so hard on yourself—you did the best you could.没必要如此苛待自己——你已经尽力了。