Questions & Answers about Das Zimmer ist sehr kalt.
How would I use nicht to say "The room is not very cold"?
You would say Das Zimmer ist nicht sehr kalt. When you negate a specific quality described by an adjective or adverb, nicht comes right before it. Here, it is placed immediately in front of sehr kalt.
Why doesn't the word kalt have an ending, like kaltes?
In German, adjectives only get special endings when they come directly in front of a noun (like in the phrase "the cold room"). When an adjective is separated from the noun by a verb like ist (is), it stays in its basic dictionary form with no extra letters.
Does the word sehr change its spelling if the noun is masculine or feminine?
No, sehr (very) is an adverb. Unlike adjectives, adverbs in German never change their endings, no matter what gender the noun is or how many things you are talking about. It is always just sehr.
Why is the article das used here instead of der or die?
Because Zimmer (room) is a neuter noun in German. There isn't a strict rule that tells you rooms are neuter, so it is always best to memorize the gender along with the noun: das Zimmer.