YOU SAID:

I should be doing other stuff

INTO JAPANESE

私は他のことをする必要があります

BACK INTO ENGLISH

I have to do other things

INTO JAPANESE

私は他のことをしなければなりません

BACK INTO ENGLISH

I have to do something else

INTO JAPANESE

何かしなければならない。

BACK INTO ENGLISH

I have to do something.

INTO JAPANESE

何かしなければならない。

BACK INTO ENGLISH

I have to do something.