1.  No international organisation is larger than the United Nations.
2. Your application cannot be accepted today.
3. The Nile is the longest river in the world 
4. The speaker who will share new learning experiences in our workshop is Laura.
5. Smartphones, which have a lot of storage space, can store audio books
6. Peter, whose sister is taking an online maths course, is a friend of mine.
7. Lan has read the book which I lent her
8. I talked to the girl whose bicycle broke down in front of the shop.
9. Thank you very much for your email, which was very interesting.
 

1.The United Nations is the largest international organisation
→No international organisation is larger than the United Nations.
2. We can't accept your application today.
→ Your application can't be accepted to day.
3. No river in the world is longer than the Nile.
→ The Nile is the longest river in the world.
4. The speaker is Laura. She will share new learning experiences in our workshop.
(who)
→ The speaker who will share new learning experiences in our workshop is Laura.
Smartphones can store audio books. They have a lot of storage space. (Which)
→Smartphones which have a lot of storage space can store audio books.
5. Peter is a friend of mine. His sister is taking an online maths course. (whose)
Peter whose sister is taking an online maths course.
The chidren were playing in the playground. They are not from our school. (Who)
→ The children who were playing in the ground aren't from our school.
6. Lan has read the book. I lent her the book. (which
Lan has read the book which I lent her.
7. I talked to a girl. Her bicycle broke down in front of the shop. (Whose)
→I talked to the girl whose bicycle broken down in front of the shop.
Thank you very much for your email. It was very interesting. (which)
->Thank you very much for your email, which was very intersting.