availability

n.可用；有效

automate, automatic, automatic pilot, automatic transmission, automatically, automation, automaton, automobile, automotive, autonomous, autonomously, autonomy, autopsy, autostrada, autumn, autumnal, auxiliary, AV, avail, avail oneself of, available, avalanche, avant-garde, avarice, avaricious, avariciously, avdp, Ave, avenge, avenger, avenging, avenue, aver, average, averagely, averse, aversion, avert, aviary, aviation,