名詞 yesterday:

1. the day immediately before today
2. the recent past

副詞 yesterday:

1. on the day preceding today
2. in the recent past; only a short time ago

1. The sound of fire-alarm was heard by us yesterday evening.
   昨晚我們聽見了火警聲。
2. I bought several books yesterday.
   我昨天買了好幾本書。
3. I wasn't born yesterday.
   我又不是三歲小孩。
4. I saw him only yesterday.
   我昨天才見到他。
5. Yesterday was Friday.
   昨天是星期五。
6. He arrived yesterday.
   他昨天到達(dá)的。

yes.ter.day

n.（名詞）
The day before the present day.
昨天：當(dāng)天的前一天
Also yesterdays Time in the past, especially the recent past.
也作 yesterdays 近來(lái)，最近：過(guò)去的時(shí)間，尤指最近過(guò)去的
adv.（副詞）
On the day before the present day.
昨天：當(dāng)天的前一天
A short while ago.
剛才，最近

來(lái)源：
Middle English
中古英語(yǔ)
from Old English geostran dôg
源自 古英語(yǔ) geostran dôg
geostran [yesterday] * see yester-
geostran [昨天] *參見 yester-
dôg [day] * see day
dôg [日] *參見 day