only [だけ replaces を, が, は and is used with へ, に, で, から, etc.]
中
[なか, チュウ] inside, middle
外
[そと, ガイ] outside
~ませんか。
Don't you~ [The Japanese answer affirmatively or negatively to the stated form of the verb rather than the action implied; ex: わかりませんか。 would be answered "Yes, I don't understand." Not to be confused with the nagative invitation form.]
いいんですか。
Is it really alright? [the んです ending is fequently used in speaking. When in question form, it invites an explaination from the listener. When used in a statement, it suggest that the speaker feels obligated to explain himself.]