What is the difference between 忘れないで and 忘れるなよ?


These two forms, ～ないで and the ～な particle seem to have similar meanings. Can
someone please explain the difference between the two?




The former （未然形+ないで） is a light negative command, the latter （終止形+な） is a
strong negative command (prohibition). （終止形+なよ） is often (not always) a
friendly / playful command.

～して ⇔ ～しないで

～しろ ⇔ ～するな

宿題をするの忘れないでね (like a mother to her child, "don't forget to do your homework")

宿題をするの忘れるなよ (depending on tone, a friendly, "you'd better not forget to do
your homework")

宿題をするの忘れるな (depending on tone, "do **not** forget to do your homework!")




The former （未然形+ないで） is a light negative command, the latter （終止形+な） is a
strong negative command (prohibition). （終止形+なよ） is often (not always) a
friendly / playful command.

～して ⇔ ～しないで

～しろ ⇔ ～するな

宿題をするの忘れないでね (like a mother to her child, "don't forget to do your homework")

宿題をするの忘れるなよ (depending on tone, a friendly, "you'd better not forget to do
your homework")

宿題をするの忘れるな (depending on tone, "do **not** forget to do your homework!")

