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to peek (through a keyhole, gap, etc.)
to look down into (a ravine, etc.)
to peek into (a shop, bookstore, etc.)
to sneak a look at; to take a quick look at
to peep (through a telescope, microscope, etc.)
to stick out (a scarf from a collar, etc.); to peek through (sky through a forest canopy, etc.)
to examine (an expression); to study (a face)
ドアの隙間からそっと中を覘いた。
I quietly peeked inside through the gap in the door.
窓から外を覘くと雪が降っていた。
I peeked outside from the window and it was snowing.
箱の中を覘いたら猫が寝ていた。
I peeked inside the box and a cat was sleeping.