1. Maire is a friend. She always helps me. {Who}
=> Maire is a friend who always helps me.
2."Why don't you ask your teacher for advice?" my brother said to me. {suggest}
=> You don't need to book tickets for the show in advance.
3. "Why don't you ask your teacher for advice?" my brother said to me. (suggest)
->My brother suggested that I (should ) ask my teacher for advice
4. His sister isn't old enough to get married. (too)
->His sister is too young to get married