Even the top students in our class cant work out this problem, so it___ be very difficult.
A. may
B. must
C. can
D. need
Excuse me. ___ you please pass me that cup?
A. Do
B. Should
C. Would
D. Must
If you want to be a polite guest,you shouldnt .
A. ask how much the hosts furniture costs
B. bring some gifts to your host
C. say anything nice about the hosts room
D. come at the right time