この時間に会社に電気がついているのは変だ。

Meaning
it is strange that the electricity is on in the office at this time

Vocab used in this sentence

この
this, these
時間
time, hours, duration
in, to, on, at, into, upon
会社
company, corporate, firm, corporation, agency, affiliates
in, to, on, at, into, upon
電気
electric, electricity, power, electrically
is, there, but, ga, will, however
つい
about, just, quite, accidentally, eventually, inevitably, inadvertently, unconsciously, unintentionally
the, it, have
いる
are, to be, to stay, to have, necessary, to exist
to, of
a, the, is, am, are, will
weird, strange, funny, odd, unusual, change, different, flat, unexpected, incident, peculiar, disturbance
is, be, are, am, it is, seems

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