Помогите плз СРОЧНО! 2.Put in: who or which.

1. She returned me the book ………… I gave her yesterday.

2. Do you know the student ………. has won the first prize in the competition?

3. The mother tongue is a language ……….. a child learns naturally, in his/ her family.

4. I knew a lady …………. ..played tennis every day.

5. Kate found a bag ……………. she liked.