.

 It is unbelievable that a well- behaved gentleman ______ be so rude to a lady.

A. will            B.may        C.must       D.should

It is unbelievable that a well-behaved gentleman ______be so rude to a lady.

   A. will      B. may      C. must        D. should

It is unbelievable that a well-behaved gentleman ______be so rude to a lady.

A．will             B．may            C．must         D．should

It is unbelievable that a well-behaved gentleman _________ be so rude to a lady．

1. A.
   will
2. B.
   may
3. C.
   must
4. D.
   should