他是你第几个儿子？

What number is he among your sons?

地球是太阳系中第几大行星？

In terms of size, what is the earth's ranking in the solar system?

地球是离太阳第几近的行星？

When we come to the question how near the planets to the sun are, where do you rank the earth?

类似的表达如：

Which page is that curry recipe on? 那道咖喱菜的做法在第几页？

Which question did you get up to in the test? 你考试做到第几题？

Which platform does the Brighton train leave from? 开往布赖顿市的火车在第几站台?

Where do you rank Wordsworth as a poet? 华兹华斯作为诗人，你把他排列第几？

Where did Peter come in—second or thirds? 彼得跑了第几名——第二名还是第三名？

What number is he from the right? 他是从右数第几个？

What number did that record get to in the charts? 那张唱片进入了排行榜的第几位？

What is his position in class?—He’s third from the top. 他在班上得第几名?——第三名。

This is the nth time I’ve told you. 这已经不知是我第几次告诉你了。