序数词应注意的几点事项:

  1. 多位数的基数词变成序数词时,只需将末位基数词变成序数词,前边的基数词不变。如:

  forty-two 42 forty-second第42

  nine-hundred 900 nine-hundredth第900

  2. 当序数词用阿拉伯数字表示时,必须在数字后加上序数词的最后两个字母。如:

  21st第21

  32nd第32

  3. 序数词前一般要用定冠词the,如果序数词前用a或an时,则表示"又一;再一"(没有具体范围的限制)。如:

  Though he had failed twice, he wanted to try a third time.

  尽管他已失败了两次,他还想再试一次。

  The little monkey had had three apples, and he wanted to eat a fourth one.

  那只小猴子已经吃了3个苹果,他还想再吃一个。