四个

• tetrad
• four

例句

1. 我们把学生分成四个组。
   We divided the students into four groups.
2. 这家百货公司有四个紧急出口。
   There are four emergency exits in the department store.
3. 他在结婚之前曾向四个姑娘求过婚。
   He wooed four girls before finally marrying one.
4. 每首诗有四个诗节。
   There are four verses in each poem.
5. 大多数汽车有四个前进挡。
   Most cars have four forward gears.
6. 辛苦工作了四个小时后，他觉得非常饿。
   He felt very hungry after four-hours' hard work.
7. 步行了四个小时以后，我们开始累了。
   After walking for four hours we were beginning to flag.