我们知道有on earth,那么有没有on the earth之说呢?如果有,它与on earth有何区别?重点回答有何区别!这里的on earth也表示"在地球上",不是什么"究竟"!

on earth究竟,到底
例句与用法:
1. Why on earth didn't you tell me the truth?
你到底为什么不跟我说实话？

2. Who on earth told you that?
那件事究竟是谁告诉你的？

3. How on earth did you know it?
你到底是怎么知道的？

4. What on earth will he get up to next?
下一步他究竟要耍什麽花样?

5. What on earth do you mean?
你到底是什么意思?

6. Who on earth is that female he's with?
跟他在一起的那个女人究竟是谁?

7. This is a market condition no force on earth can change.
这一市场情况任何力量也改变不了。

8. What on earth is that?
这到底是什么?

on the earth:
在地球上

例句与用法:
1. Scientists have set up two kinds of relay stations. One kind is on the earth, the other is a satellite placed in space around the earth.
科学家们已建立了两种中继站，一种在地球上，而另一种是放在地球周围太空中的卫星上。

2. Long ago enormous animals lived on the earth.
很久以前，地球上生活着巨大的动物。

3. There are millions of living things on the earth.
世界上有数以百万计的生物。

4. If it were not for oxygen and nitrogen in the air, no man could live on the earth.
大气中如果没有氧和氮，人就无法生存于地球了。

on earth 和 on the earth 都有在地球上的意思
on earth 还有究竟的意思