to

[puzzle]

Mongolia is on the north of China.

Is it right to replace "on" by "to"? Please.

[5jj]

'To' is the natural preposition here; 'on' is not.

[puzzle]

I'm not sure what's your meaning, it's wrong with "to" here? Would you explain more? Please.

[Barb_D]

Simply:
To is right.
On is not a common way to say this.

[faryan]

Simply:
To is right.
On is not a common way to say this.

Is it a general rule? Shall we use the proposition "to" in the case of talking about locations on a map ?

[Rover_KE]

Puzzle, note that Mongolia is on/to the north of China would have been a better title for this thread.

You can say 'Mongolia is to the north of China' or 'Mongolia is north of China'.

(Point of information: parts of Mongolia are situated to the east and west of China.)

Rover

[Rover_KE]

Is it a general rule? Shall we use the preposition "to" in the case of talking about locations on a map ?

Yes.

[5jj]

Is it a general rule? Shall we use the proposition "to" in the case of talking about locations on a map ?

It depends on what you want to say.

Portsmouth is in to the south of England.