1.practice 后必須跟動(dòng)名詞作賓語(yǔ).
2.by 在……之前.用at來(lái)表示在某一時(shí)刻,at 4∶30在4點(diǎn)30分;
by a time＝at that time or before／not later than that time
在那一時(shí)刻或在那一日期或不遲于那一日期
這種表示方法常暗指在那一時(shí)刻之前
The train starts at 6∶10,so you had better be at the station by 6∶10.
火車6點(diǎn)10分發(fā)車,所以你最好在6點(diǎn)10分之前到達(dá)火車站.
3.have fun doing sth.:做某事很開心 = have a good time doing sth.= enjoy
doing sth.