My native language is Portuguese, and that was a bit of an impediment for playing some games when I was a kid, but I believe Lucasarts adventure games thought me most of my English. I really can't remember when I knew it well enough to play those games, but I do remember playing them with my brother when I was 7 or 8 and he was 12 or 13 and that being very significant. Before that, all I could read was "press start button", "options", "easy", "hard", "game over", "congratulations", "thank you for playing", "the book is on the table", those kind of things. That learning is pretty understandable, and it's been several years since I realized that. Adventure games back in the day not only obligated you to read full dialogues to find out what you had to do next, but you also had to choose what you'd say and make sense with that. It also thought you to verbalize, creating full sentences for your actions ("Pick up mug", "use mug with barrel o' grog", "walk to the sun"). Later, since Sam and Max Hit the Road, I believe, with those games becoming more and more intuitive and getting rid of the HUD filled with verbs, that was lost. Nowadays you have no verbalizing of any kind, with the same kind of click doing the "look", "pick up" and "use", and that makes sense, I mean if you click a door you probably want to open it, close it or go through it, but I always felt that some richness there was lost. It also made those games a lot easier, since you have many times less possibilities for your actions.