.---There is a lot of smoke coming out of the teaching building.

---Really? It _____be a fire, most probably.

A. can       B. ought to    C. have to       D. must

—There is a lot of smoke coming out of the teaching – building.

—Really? It         be a fire.

A．can   B．ought to    C．have to     D．must

—There is a lot of smoke coming out of the teaching building.

—Really? It _____be a fire, most probably.

A. can       B. ought to    C. have to       D. must

---- There is a lot of smoke coming out of the teaching-building there.

---- Really? It _____ be a fire, most probably.

A. can      B. ought to       C. have to      D. must

—There is a lot of smoke coming out of the teaching-building there.?

—Really?It _________ be a fire,most probably.?

A.can             B.ought to             C.have to        D.must

—There is a lot of smoke coming out of the teaching-building there.

—Really?It______ be a fire,most probably.

A.can                           B.ought to

C.have to                   D.must

---- There is a lot of smoke coming out of the teaching-building there.

---- Really? It _____ be a fire, most probably.

A. can      B. ought to       C. have to      D. must

---There is a lot of smoke coming out of the teaching-building there．

---Really?It ________ be a fire, most probably．

1. A.
   can
2. B.
   ought to
3. C.
   have to
4. D.
   must

— There is a lot of smoke coming out of the teaching building there.

— Really? It _________ be a fire, most probably.

A. ought to           B. can            C. have to        D. must