もう、さっきからブンブンと、うっとうしいハエだなあ。

Meaning
hmph, these flies have been buzzing for a while now, how irritating

Vocab used in this sentence

もう
already, more, another, again, now, anymore, yet, longer, soon
さっき
just, a moment ago, just now
から
from, at, because, out of, by, since, off, after
ブンブン
buzz, buzzing, whirring, humming, hum
and, with, if
うっとうしい
annoying, tedious, irksome, dreary, dull, drearisome
ハエ
flies, fly, housefly
is, be, are, am, it is, seems
なあ
wish, look, hey, well, listen

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