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to open (a door, etc.); to unwrap (e.g. parcel, package); to unlock
to open (for business, etc.)
to empty; to remove; to make space; to make room
to move out; to clear out
to be away from (e.g. one's house); to leave (temporarily)
to dawn; to grow light
to end (of a period, season)
to begin (of the New Year)
to leave (one's schedule) open; to make time (for)
to make (a hole); to open up (a hole)
「開ける」 has other readings with different meanings.
窓を開けてもいいですか。
May I open the window?
プレゼントの箱を開けてみた。
I tried opening the present box.
ドアを開けたら冷たい風が一気に入ってきた。
When I opened the door, cold wind rushed in all at once.