1. When I was a child, I liked watching cartoons but now I no longer like them.

=> When I was a child, I used to like watching cartoons
2. My brother is very lazy. I can’t stand him anymore.

=>  I wish my brother wasn't very lazy
3. I want to be a university student but I can’t.

=> I wish I was a university student
4. When Jim was six, he dreamt of becoming a superhero but now he gives up on that dream.

=> When Jim was six, he used to dreamt of becoming a superhero