n.不久前;往昔;
adv.昨天;
例句:
Yesterday I went to see him, but again he wasn't home.
昨天我去找他, 又扑空了.
Where were you yesterday morning?
你昨天上午在哪儿?
All her yesterdays had vanished without a trace.
她的过去已经完全烟消云散了。