Problem with the たい form

Question

I was reading yotsubato! and I had a bit of trouble with this,The English translation Says that it means I wanted ice cream but I thought that the past for of want was たかったです

Answer 1

I would say that the English translation did not translate the phrase literally, and that's where the confusion kicked in. The original reads:

アイス食べたくなったから…
I wanted icecream, so...

Here, the construction is 食べたい + なる, meaning "to become wanting to eat". So, a more accurate translation would be

アイス食べたくなったから…
I became wanting to eat icecream, so...
(More natural to English speakers) I became icecream-craving, so...

The verb that's put into past tense is なる, and "wanting to eat" is now an adverbial phrase, which is tenseless. You're right about that past tense of 食べたい being 食べたかった, but that would just mean "I wanted to eat", not "I became wanting to eat". The なる/became signifies a transition in state, both in English and in Japanese.

Of course, you could say the "transitioning" nuance is lost in translation, but you can see why the translator did not chose to translate it all out, because it kinda feels bulky and unnatural in English. However, in Japanese it's perfectly normal.

Grammar Summary

You probably know this already, but なる means to "to become", and you can become a NOUN, or an ADJECTIVE. To become a noun or an な-adjective, simply use に before なる, to become a い-adjective, change the い into く, which is the adverb form thereof.

I wanna become the president.
大統領になりたい。(大統領 + なる)
This should be/become more secretive.
もっと密かになるべきだ。(密か + なる)
I wanna get/become faster than him
彼より早くなりたいな。(早い + なる)

So yeah, 食べたい + なる would then be 食べたくなる.