单项选择题
The numbers in the key do not correspond （） those in the lessons.
A.for B.to C.on D.at
单项选择题 Send your questions to Mary Adams,（） is the director of Public Relations,for a quick reply.
单项选择题 Our Accounts Receivable Department has written to you three times;（）,we have had no response to our letters.
单项选择题 （）in the labor market,he has enrolled in a computer course.
