[xū]
[名]
（空虚） void; emptiness
infiltrate by taking advantage of the other side's unpreparedness; exploit a weak point
乘虚而入
soar to the skies
凌虚
the great void; the universe
太虚
（政治思想等方面的道理） guiding principles; theory
discuss principles or ideological guidelines
务虚
Let correct ideology guide practical work.
以虚带实。
（二十八宿之一） Xu, one of the lunar mansions
（姓氏） a surname
Xu Zigao
虚子羔
[动]
（空着） reserve space
reserve the honoured post for someone competent
虚左以待
[形]
（空着的） empty; void; unoccupied
There was no empty seat.; All seats were occupied.
座无虚席。
（心虚； 勇气不足） diffident; timid
timid; milk-livered
胆虚
feel rather diffident
心里有点虚
（不真实； 虚假） false; nominal
false reputation
虚名
What you hear about may be false; what you see is true.
耳闻为虚， 眼见为实。
（不自满； 虚心）humble; modest
modest
谦虚
（虚弱） weak; in poor health
lacking in vital energy; sapless
气虚
be very weak physically
身体很虚
He felt very weak after his illness.
他病后感到很虚。
[物] （虚的） virtual
virtual placement
虚位移
virtual cathode
虚阴极
[副]
（徒然； 白白地） in vain
have not made the trip in vain
不虚此行
Not a single arrow missed its target.
箭不虚发。