单项选择题A．The woman received a phone call from Mark yesterday.B．The man injured Mark in a traffic accident yesterday.C．The man met a friend of theirs by chance.D．The woman contacted Mark on business.

单项选择题A．The visiting economist has given several lectures.B．Dr. Johnson and the guest speaker were schoolmates.C．Dr. Johnson invited the economist to visit their college.D．The guest lecturer’s opinion is different from Dr. Johnson’s.