Definition: to make someone become unconscious, usually by hitting them on the head Level: B2
他在拳击比赛中途被击倒了。
He was ___knocked ___out halfway through the boxing match.
保安对闯入者的头部一击，便将其打晕。
The security guard ___knocked the intruder ___out with a single blow to the head.
拳击手在第二回合击晕了对手。
The boxer ___knocked his opponent ___out in the second round.
