No, "most friendly" is not grammatically correct. The correct form would be "friendliest" when comparing three or more things.
Yes, the sentence "He is their most targeted receiver" is grammatically correct. It means that he is the receiver who gets the most passes thrown to him by his team.
No. It is my favorite place is the correct spelling. Most is implied in favorite.
No, it is not. It would be either most sweet, or sweetest.
correct. but one religon seems to have the most terrorists.
Yes, "most preferable" is grammatically correct. It is a comparative form that indicates the highest level of preference in a given context.
The green moss was most slippery when it was wet.
Yes, you can say that in correct English. One of the most cutest is grammatically correct.
Yes.
Yes, "fastest" is a grammatically correct superlative form of the adjective "fast." It is used to show that something is the most speedy or quick in comparison to other items or entities.
It doesn't look grammatically correct, but not everything that is correct looks that way. When you break the sentence apart, there is nothing missing. It has a subject and a predicate. Although "You are the winner" may be more appealing to most people, I do not believe there is anything grammatically incorrect with your example, as ugly as it may sound. It is correct. You can be be a subject or an object pronoun. subject - You are the winner! object - The winner is you!
No, "most catchiest" would be redundant. Catchiest already makes a thing the most or best. Use most only when you are not using a word that already implies most. It was the catchiest slogan the Republicans could offer. It was the most catchy line he could think of.