The hyphen would normally be omitted for both. For me, 'sparsely populated' is the more common expression. 'Scarcely populated' isn't really right. It's a wrong use of words - but it's not a grammatical mistake.
"God help you" is the correct phrase, as it is a traditional expression of sympathy or encouragement. It is not a grammatically correct sentence, but rather an idiomatic expression.
"I am friends with X" is correct."We are friends" and "X and I are friends" are also correct."I am friend with X" is not correct.
No, Belying her utter terror, Natalie maintained a calm expression is correct.
Yes, 'for free', is grammatically correct.
"Not like that" can be grammatically correct, depending on the context.
Yes! That is grammatically correct!
Yes, "May God bless him" is a correct and polite expression. It is often used to convey good wishes and blessings to someone.
This is not grammatically correct. The correct form is 'you do not know', or the abbreviated 'you don't know'.
It is not grammatically incorrect, but not right, either. We say wishes come true.
Yes, the sentence is grammatically correct. It conveys a positive expression of anticipation to meet a group of people in the future.
'What a drunkard you are' is a grammatically correct English sentence.
"That was wrong" is a grammatically correct sentence.