yesterday
1.on yesterday似乎只用在美国。
2.yesterday在记事里有时指上文说起过的某天的昨天。例如：We got a better chance than we had had yesterday.
3.all yesterday不及all day yesterday合乎习惯。
4.yesterday morning和yesterday afternoon里的yesterday不可改作last。yesterday evening和last evening都可以说。yesterday night不及last night普通。
