Carp fish leaping through the dragon's gate
Carp fish, dragon's gate:

Add leggs to the snake

Wait for a hare to turn up 

the fox borrows the tiger's fierceness

The Lord Ye loves Dragon

Blessing or Bane

A Foolish Man Buys His shoes

A Mantis Trying to Stop a Chariot

No More Tricks, Mr. Nan guo!

plucking up a crop to help it grow

The proverb "carp fish leaping over the dragon's gate" li3 yu2 tiao4 long2 men. 

Lengend has it that each Chinese carp would swim up the yellow river upstream to spawn, and those who can leap the waterfall at the dragon’s gate were transformed into dragons.

The meaning of this proverb, simply is, if a person works hard at whatever he does, he could one day become successful. This proverb is used to encourage a person to persist in one’s endeavor. 

In the past, a carp leaping over the dragon’s gate was used as a metaphor for success in passing the imperial exams.