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を自慢するのももっともだ

it's no wonder … is proud of

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phrase Rare #30,767
it's no wonder … is proud of The phrase means that it is understandable or only natural for someone to be proud of or boast about something.
JA: 彼が成績を自慢するのももっともだ。
EN: It's no wonder he's proud of his grades.

彼がお父上を自慢するのももっともだ。

It's no wonder he's proud of his father.

彼女が息子を自慢するのももっともだ。

It's no wonder she's proud of her son.

彼女が自分の才能を自慢するのももっともだ。

It's no wonder she boasts about her talent.

彼が自分の娘を自慢するのももっともだ。

It's no wonder he's proud of his daughter.

彼が息子達を自慢するのももっともだ。

It’s no wonder he’s proud of his sons.

彼女が息子のことを自慢するのももっともだ。

It's no wonder she's proud of her son.