What is the て form of しない?


The hypothetical scenario is given as follows.

  * Yesterday night I played game and intentionally did not do the homework. I did not forget for sure. :-)
  * This morning the teacher asked me and I want to pretend to regret what I did.

From this scenario, I want to say something that makes use of ～てしまいました
grammar.

> 宿題を[the て form of しない]しまいました。

What is the て form of しない ?




しないで would be the て form of しない, but in conversation you don't hear the
negative form of a verb used with しまいました. Instead you use the positive form of
a verb + て form + しまいました. So for example, 宿題をしてしまいました would emphasize that you
did your homework. If you didn't do the homework you need to connect it's
negative with another verb. For example, 宿題をしないで来てしまいました。

