Grammar JLPT Level N4 - Lesson 2

There are two primary ways in which ないで is used with verbs in Japanese. The first is to express 'without doing (A), (B)'. The second is to request that someone 'not do (A)'. We will examine the first in this write-up.
ないで is a combination of the auxiliary verb ない, and the particle で. Due to this, で keeps its standard meaning of 'with/by', in relation to 'not' doing something.

• 魚(さかな)を焼(や)かないで食(た)べたから、お腹(なか)を壊(こわ)した。
  Since I ate fish without cooking it, I got a stomach ache. (Literally, to break one's stomach)
• アミはドアのカギをかけないで寝(ね)るの？危(あぶ)ないよ。
  Ami, you sleep without locking your doors? That's dangerous.

When ないで is used to express that '(A) has not been done before doing (B)', this is usually contrary to some kind of expectation. Because of this, ないで is often used to express something that may be surprising to the listener.

• 上司(じょうし)に伝(つた)えないで休(やす)んだの！？
  You took the day off without notifying your boss!?