Answer:
11. Many are called (but few are chosen.)
12. I will call you (to help the needy.)
13. My big brother (is my defender.)
14. Do you agree (with his proposal.)
15. (He dreams of) becoming a teacher.
16. (I was so thin) when I was a kid.
17. It feels so nice (when I got home tonight.)
18. We both agreed (to keep our secret.)
19. I'm so lucky (to have a great friend like you.)
20. Do you want (to join our group.)
There you go