HE SHOULD KNOW HOW (USE)... THE LIFT, BUT IF HE DOESN’T YOU’D BETTE...

3. - KIEM TRA ANH VAN 8 KII
KIEM TRA ANH VAN 8 KII
3. He should know how (use)... the lift, but if he doesn’t you’d better (show) ... him.V. change into reported speech (3M)