僕は妻を選ぶのに大変な間違いをした。

Meaning
i made a terrible mistake in choosing my wife

Vocab used in this sentence

僕
i, me, myself, servant, manservant
は
a, the, is, am, are, will
妻
wife, my wife, his wife
を
o, the, to, wo
選ぶ
choose, pick, opt, elect, select
の
to, of
に
in, to, on, at, into, upon
大変
very, hard, tough, difficult, dreadful, serious, terrible
な
a, the, na, nan, nai
間違い
mistake, no doubt, wrong, definitely, error, fault, slip
を
o, the, to, wo
し
and, shi, four, death
た
the, was, ta, da, other

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