Choose the best answer: active or passive

----- Nội dung dịch tự động từ ảnh -----
I/ Choose the best answer: active or passive
6. This burnt out light bulb (bóng đèn cháy)....days ago. Could you do it
for me?
A. might be replaced
B. might have been replaced
C. should have been replaced
D. should be replaced
7. You'd better not drink that river water. It
A. could be polluted
B. could pollute
C. can be polluted
D. can pollute
8. I think everyone.
It contains information that everyone should have.
A. should be read
B. should read
C. should have been read
D. should have read
9. Your passport.
ký).
A. is supposed to sign (ký tên)
B. is supposed to be signed
C. was supposed to sign
D. was supposed to be signed
..this paperback (sách bìa mềm) on the economic crisis.
It is invalid(vô hiệu lực) without your signature (chữ