It is not a sentence. There is no main verb.
'Energy of a substance which always remain stationary' is not a correct statement
This sentence is grammatically correct.
Yes, it is.
The sentence (not sentance) is grammatically correct
You had not taken that into account. Would be the grammatically correct version of that sentence.
No, the sentence is not grammatically correct. It should be written as "Here is my work schedule for this week."
Der Junge ist rothaarig is grammatically correct.
No, "firsts" is not grammatically correct. It should be "first."
yes
This sentence is not grammatically correct. For the sentence to be grammatically correct, the space between "in" and "to" would have to be removed. Therefore the sentence should read "They are into skating."
"That was wrong" is a grammatically correct sentence.
The sentence is not grammatically correct. It should be written as "Can you have the sheriff serve the subpoena?"
The sentence is grammatically correct.