Find the mistake

Mark the letter A, B, C, or D to indicate the underlinea part ma
questions.
31. When I turned on my computer, I was shocked to find some junk mails, so I delete them all.
B
C
D
32. You had better to change your attitude to work in order to have good performance.
A B
C
D
33. If you do morning exercise regular, you will become stronger.
A
B
C
D
D
34. The apartment on the 22nd floor was quickly sold to their new owner.
A
B
C