About the te form (てもいいです/なくではいけません）

[alvisspeaking]

皆さん，こんにちわ！

I am not sure if my questions are about the te form or not (that's how beginnerish i am lol), but here goes:

Below are a few sentences that throw me off:

(1)中古車でもいいです。　I am currently learning "てもいいです”. Does this sentence imply that to say something (noun) is acceptable, i can just put whatever the noun is before ”でもいいです”, meaning that thing is OK/acceptable?? 　The て being conjugated to で？？

(2)新車じゃなくてはいけません。　　I know なくてはいけません means "must be...", but why じゃ？Does this structure "noun+じゃなくてはいけません”　applies to all nouns??

(3)ルームメートがいてもいいですか。 What does がい function in this sentence?


どうも！ Thanks in advance for your time and efforts.

I look forward to hearing from you all

Best

Alvis
　

[community.japanese]

Alvisさん、
こんにちは。That is the correct spelling.
You can ask questions anywhere.

(1) noun is followed by でもいいです.
verbて form + もいいです for example, 食べてもいいです　and 行ってもいいです. However,as you know verbて form sometimes has　で, for example, 読んで. So it becomes 読んでもいいです.

(2) Yes. Noun is followed by じゃなくてはいけません or　でなくてはいけません (more polite than the first one).

(3) Unfortunately you divided sentences wrongly.
ルームメート　　が　いても　いい　です　か
Have you learnt particles? が is a particle.
いても comes form いる which means “to be or to stay”.
That is the te-form + conditional も.
Therefore, the meaning is “is it ok if my roommate is there?”.

Yuki 由紀
Team JapanesePod101.com

[alvisspeaking]

Alvisさん、
こんにちは。That is the correct spelling.
You can ask questions anywhere.


(3) Unfortunately you divided sentences wrongly.
ルームメート　　が　いても　いい　です　か
Have you learnt particles? が is a particle.
いても comes form いる which means “to be or to stay”.
That is the te-form + conditional も.
Therefore, the meaning is “is it ok if my roommate is there?”.

Yuki 由紀
Team JapanesePod101.com

こんにちは，yuki先生！　どうもありがとうございます！　わかりました！