haha wa watashi no goukaku o yorokobimashita.

My mother was happy about my passing.

Breakdown of haha wa watashi no goukaku o yorokobimashita.

• は: topic particle
• 私わたし: I
• を: direct object particle
• の: possessive case particle

Questions & Answers about haha wa watashi no goukaku o yorokobimashita.

Why is 母 used here instead of お母さん?

母 is the plain word for my mother when talking about your own mother to someone else.

A common pattern is:

• 母 / 父 = used for your own mother/father when speaking to outsiders
• お母さん / お父さん = used when directly addressing your mother/father, or sometimes when referring to someone else’s mother/father more politely

So in this sentence, 母は... is the natural choice if the speaker is telling someone else about their mother.

What does は do in this sentence?

は marks the topic of the sentence.

So 母は means something like:

• As for my mother, ...
• My mother, ...

It tells the listener that the sentence is going to say something about mother.

In this sentence:

• 母 = mother
• は = topic marker

So the rest of the sentence explains what is true about her: she was pleased about the speaker’s passing.

Why is it 私の合格? What does の mean here?