昨日
Today is Friday, so yesterday was Thursday.
♔基本Today is Friday, so yesterday was Thursday.
きょうは金曜だから, 昨日は木曜だった.
Yesterday was very cold. (=It was very cold yesterday.)
Yesterday was very cold. It was very cold yesterday.
昨日はとても寒かった.
⦣ （ ） 内の文の yesterday は副詞. It は漠然ばくぜんと「気温」を表す.
I called him yesterday morning.
I called him yesterday morning.
私は昨日の朝彼に電話をした.
⦣ 「昨日の朝～した」という時, ×on yesterday morning などと前置詞をつけない.
The news was in yesterday's paper.
The news was in yesterday's paper.
そのニュースは昨日の新聞に出ていた.
It's already yesterday's news.
It's already yesterday's news.
それはもう昨日のニュースだ.
⦣ 「もう古い話だ」の意味. 