Does 「静かではなければいけない」mean "must be quiet"?


I know I can use 「なければいけない」with verbs to mean "must/have to", but can I use it
with adjectives/ nouns in this manner:

> 「家を買うといえば、近所は静かじゃなければいけない」

Conversely, to say "must not" with adjectives/nouns, would I say something
like

> 理想の彼氏は、怠惰ではいけない

based on the fact that one uses the same structure with verbs, such as
「そこに入ってはいけない」.

If I am completely wrong, and there is a more normal way to say "must be/has
to be" with adjectives/nouns, please let me know.




Yes, you can safely say 静かじゃなければいけない, 静かでなければいけない, 怠惰じゃいけない and 怠惰ではいけない. You
can use this construction with arbitrary ordinary nouns, too.

By the way, ～といえば tends to mean "Now that you mention ～" or "～ reminds me".
Perhaps you wanted to say 家を買うということなら ("when it comes to buying a house")?

