Asu shigoto ni ikanai to ikemasen
Several variations in Japanese express ‘should,’ ‘must,’ and ‘need to,’ all of which convey the obligation or necessity to do something. These forms are often used with the short negative form (nai-form) of verbs.
For example, expressions like ‘…nakereba naranai’ or ‘…nakutewa ikenai’ both mean ‘must’ or ‘have to,’ where the verb is conjugated into its short negative form ‘nai-form’.
Here we take a look at the variation.
…nakutewa ikemasen
…nakutewa damedesu
…nakereba ikemasen
…nakereba damedesu
…nakya ikemasen
…nakya damedesu
…naito ikemasen
…naito damedesu
Although all the forms are used but here we learn the last two types, as it’s more simple.
…nai to ikemasen, …nai to damedesu
nai-form + to + ikemasen (you don’t do, then, not OK >>> need to do)
nai-form + to + damedesu (you don’t do, then, not OK >>> need to do)
“ikemasen” and “damedesu“ mean prohibition.
With a verb “iku” (go)
ikanai to ikemasen (you need to go)
ikanai to damedesu (you need to go)
In conversation “ikemasen” and “damedesu” are sometimes omitted.
Expression
Mou osoi node, kaeranai to ikemasen. (As it is already late, I need to go back home.)
Gomi wa gomibako ni sutenai to damedesu yo. (You should throw trash into the trash can.)
Ashita wa oosaka ni ikanai to ikemasen. (Tomorrow, I need to go to Osaka.)