a problem about earth
on the earth or on earth
'zai4 di4 qiu2 shang'
if someone said ,' what's on earth?' he would mean 'jiu1 jing4 fa1
sheng1 le1 shen2 me1?'
what's difference between them.

Question

a problem about earth
on the earth  or on earth 
'zai4 di4 qiu2 shang'
  if someone said ,' what's on earth?' he would mean 'jiu1 jing4 fa1
sheng1 le1 shen2  me1?'
what's difference between them.

Answer

use "the" before any word, means it is unique in the world, so "on the earth" means  "zai4 di4 qiu2 shang4".
"on earth" is a fixed collocation

Answer

'zai4 di4 qiu2 shang'
means 在地球上
'jiu1 jing4 fa1
sheng1 le1 shen2 me1?'
means 究竟发生了什么？

Answer

Also... "What on Earth..... (.... are you doing? / ... is that? ...etc) stresses the peculiarity of said action / thing.

Answer

"What on Earth?!" is an exclamation of surprise. It is a rhetorical question. An expression not to be take literally.

Also see "What the hell?!", "What the heck?!" "What the fuck?!" or "What the!"  etc...

Answers · 5

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