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to hit
to expose
to apply (e.g. patch); to put on; to put against; to hold on; to hold against
to allot; to call on someone (e.g. in class)
to guess (an answer)
to make a hit (e.g. in a lottery)
熱があるので濡れタオルを額に当てて休んだ。
I rested with a towel applied to my forehead.
犯人を当てるクイズをやった。
I did a quiz to guess the culprit.
光を鏡に当てて反射させる実験をした。
I shone light on a mirror to reflect it.