君は入ってはいけない。

君は入ってはいけない。

You must not come in.

君(きみ)は入(はい)ってはいけない。

Kimi wa haitte waikenai.

君 (きみ)

you; buddy; pal; monarch; ruler; sovereign; (one's) master

は (は)

topic marker particle; indicates contrast with another option (stated or unstated); adds emphasis

入る (いる)

to get in; to go in; to come in; to flow into; to set; to set in

ば (ば)

if ... then; when; and; why don't you...?; the more (one does something); because; since

Readings: クン、きみ、 -ぎみ

Meanings: mister, you, ruler, male name suffix

Readings: ニュウ、ジュ、い.る、 -い.る、 -い.り、い.れる、 -い.れ、はい.る

Meanings: enter, insert