Verbs · N5
ます form vs dictionary/plain form
Politeness and grammar structure are separate choices.
In short
ます creates a polite verb predicate. The dictionary/plain form is the basic non-past form used in casual speech and inside many larger grammar patterns.
How it works
食べます and 食べる both describe eating in non-past contexts, but differ in register. Before nouns and many grammar endings, plain forms are required even inside otherwise polite sentences.
Useful contrast
Plain does not automatically mean rude. It is the structural base for clauses, and register depends on the whole interaction.
Examples
毎日勉強します。
I study every day. (polite)
毎日勉強する。
I study every day. (plain)
Common pitfall
Do not attach です after a plain verb as a general politeness fix: *食べるです is not standard.