UNIT 49I. PRONUNCIATION

31. - 3500 CAU TRAC NGHIEM ON TAP AV THCS
3500 CAU TRAC NGHIEM ON TAP AV THCS

31. My father allowed me to invite my friends for dinner. He said: "

You ... invite your friends for dinner tonight".

a. ought to

b. have to

c. must

d. may

 d