What form does 会いたくなる belong to?


I am confused with the word form 会いたくなる belongs to.

This phrase is found in this sentence:

> ひとりでいると 会いたくなるよ

So far, what I know:  
会う: meet  
会いたい: want to meet

But I don't know what is 会いたくなる and how this phrase is formed?




> 「Verb in 連用形{れんようけい} (continuative form) + たくなる」

means:

> "to get the urge to (verb)"

You will keep encountering this pattern for as long as you study Japanese.

The verb 「なる」 always expresses a change of state; It is a key verb in the
language. I could not live one day without using 「なる」 at least 20 times just
as an English-speaker could not live a day without using the verb "to get" at
least 20 times. 20 would probably be an understatement, too.

Notice that both 「会い」 and 「たく」 are 連用形 of 「会う」 and 「たい」, respectively. 連用形 is
extremely important and that is why I have to say "連用形{れんようけい} (continuative
form)" all the time here even if it takes me a long time to type all that each
time.

So, the sentence in question means:

> "I get the urge to see you when I am alone."

