お母さん が 来ないの が 分かりました。okaasan ga konaino ga wakarimasita.
I understood that your mother wouldn't come.

Breakdown of okaasan ga konaino ga wakarimasita.
がga
subject particle
来るkuru
to come
お母さんokaasan
mother polite
分かるwakaru
to be understood; to understand; to be known
のno
verb nominalizer
Elon.io is an online learning platform
We have hundreds of Japanese lessons and thousands of exercises.
