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only; merely; nothing but; no more than
approximately; about
just (finished, etc.)
as if to; (as though) about to; going to; on the point of; at any minute
indicates emphasis
always; constantly
「許」 has another reading with different meanings.
彼は文句ばかり言っている。
He does nothing but complain.
最近は雨ばかりの日が続く。
It has been nothing but rainy days lately.
忙しくて寝てばかりもいられない。
I am too busy to just sleep all the time.