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to cover; to hide; to conceal; to wrap; to disguise
恥ずかしくて両手で顔を掩った。
I was embarrassed and covered my face with both hands.
砂嵐が町全体を掩ってしまった。
A sandstorm engulfed the entire town.
落ち葉が道路を掩って滑りやすくなった。
Fallen leaves covered the road and made it slippery.