expressions:
knock at敲打
knock off 碰掉，I knock the vase off the table
下班，He always knocks off six o'clock.
打折，knock 10% off the bill 其中off后边需要加sth
knock over，撞到knock sb over
knock out，把人打昏，knock sb out
in return for this 作为回报
stand on one's head 倒立
He calls at every house in the street
words:
unconscious，adj，无意识的，失去知觉的，不省人事的，未发觉的
也可以表示潜意识
adv
unconsciously，不知不觉的，无意识的
n
unconsciousness，无意识，意识不清