3.I don't know the song which are they singing.
6.They are the children who won the match.
19.A global is a ball which has a map of the world on it.
20.The soup was too salty which I had it for lunch.
23.Ms Kim Anh who you talked with yesterday will be our history teacher next semester.
24.The watch belongs to Lam which is in the bathroom.
47.There are some words which they are very difficult to translate.
49.A pacifist is a person who believes that all wars are wrong.