It's the company which because "who" is for a person, "which" is for a thing. Companies are things, not people.
It sounds better to use "that". For example: The company that polluted the river was ordered to clean it out within two years.
Yes, Almighty God is grammatically correct.
"That was wrong" is a grammatically correct sentence.
Yes, it is grammatically correct.
This sentence is grammatically correct.
No, it is not grammatically correct. If you want someone to correct it for you, please can you explain what you are trying to refer to?
"went out in the company of your friends" is correct.
My company has entered into.....
Group of companies is grammatically correct.
If you use "with" it indicates there's a company of friends and you went with them. If you use "in" it indicates you are part of the company.
"Not like that" can be grammatically correct, depending on the context.
Yes it is a grammatically correct
Yes! That is grammatically correct!
Yes, 'for free', is grammatically correct.
This is not grammatically correct. The correct form is 'you do not know', or the abbreviated 'you don't know'.
"That was wrong" is a grammatically correct sentence.
Yes, it is grammatically correct.
Yes, Almighty God is grammatically correct.