Translation:He has a headache and he needs to rest.
This is strange...I put "His head aches, he needs to rest" and it was marked wrong; the correct answer was shown as "His head hurts he needs to rest."
Teng means "ache" so "his head aches" seems an appropriate option.
Ache isn't used so much as a verb in English the way you're using it. It's more idiomatic to use "hurts".
would "he has a headache so he needs to rest" be correct? it was marked wrong for me
The "correct" answer I was shown ends with "he's rest", which is definitely not correct.
He's is a contraction for "he is." In that case, you mean to say "he is resting" or "he's resting."
"His head hurts," would be a more direct translation here.
Also general question: is the 很 necesarry here if 头疼 means headache as is? I was always just taught to say "我的头疼。"
For reference, "His head hurts very much, he needs to rest" was accepted
The correct response is apparently "He has a headache , he's rest." I've reported it of course for incorrect English.
So 休息 is like resting when you are sick. And 轻松 is like resting from stressful work. Am I right?
休息 simply means to rest, regardless the context. 轻松 can be used as a verb but more often is used as an adjective. (the characters literally mean "light" and "loose"). Here are a couple of sentences to give you the feel: 我要回家休息 - I will go home and rest. 我的工作今天比较轻松 - My work was relatively relaxed today.
The 'he' doesn't need repeating. 'He has a headache and needs to rest' should be accepted. The Chinese doesn't repeat 'he' and it isn't necessary to do so in English either.