彼はうっかり猫を家の外に出してしまった

Meaning
he let the cat out of the house by accident

Vocab used in this sentence

he, his, him, boyfriend
a, the, is, am, are, will
うっかり
accidentally, inadvertent, inadvertently, careless, carelessly
cat, neko, feline
o, the, to, wo
house, home, family, building, residence, dwelling, residency, habitation
to, of
outside, other, outdoors, foreign
in, to, on, at, into, upon
出し
out, serve, present, pretext, submit, release, excuse, stock, sauce, broth
the, it, have
しまう
get, end
the, was, ta, da, other

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