how the mountain grows?

I only know of two ways that a mountain grows. One is if it is volcanic, growing on its own ejection of lava. Another would involve two of earth's tectonic plates exerting pressure on each other, pushing the mountain up.

http://en.wikipedia.org/wiki/Continental_collision

I hope this helps. Thanks for asking.

there's 2 types of wayz a mountain grows. diverging plates and converging plates
diverging plates push together and push the mountain up
converging is when one plate goes under the other plate and the other plate makes a monutain

hope it helps