四し月がつ

し

が

つ

Meanings

1

April

The fourth month of the Gregorian calendar; the start of the fiscal and academic year in Japan.

2

fourth month of the lunar calendar

Historical or traditional use; roughly corresponds to May in the modern calendar. Rare in everyday conversation.

４し月がつになるfor it to become April
もう４月がつになりましたね。
It's already April, isn't it.
４し月がつから〈事こと〉が始はじまるfor something to start from April
新しん学がっ期きは４月がつから始はじまる。
The new school term starts in April.
４し月がつに入にゅう学がくするto enter school in April
妹いもうとは４月がつに小しょう学がっ校こうに入にゅう学がくする。
My little sister will start elementary school in April.

卯う月づき sense 2
四月 is the modern Gregorian-calendar name for April, while 卯月 is the old poetic name used for the fourth lunar month.

七しち月がつN5
七月 (しちがつ, July) and 四月 (しがつ, April) sound very similar because of the し/しち contrast, so learners often mishear or mispronounce one for the other.
四よ月つき
四月 (よつき) means 'four months' while 四月 (しがつ) is the calendar month 'April'; only the reading tells them apart.

四し月がつ
Standard kanji spelling, preferred in vertical text and formal documents.
４し月がつ
Common in horizontal writing and digital contexts; functionally equivalent to 四月.

Compound of 四 (four) and 月 (month). The reading しがつ is a regular on'yomi combination.