Fill in the correct prepopsitions:
1) ___ request 2)to be suitable__ smth 3)to wander ___ 4)to concentrate__ smth
5)to be responsible __ smth 6)to participate __ smth 7)all__ all 8)to prevent sb _
doing smth 9)to suffer __ smth 10)to be dependent __ smth 11)to protect smb__
smb 12)to be ideal __ smb