—Have you known each other for long?—Not very long we started to work in the company.A. a

问题补充：

—Have you known each other for long?

—Not very long, we started to work in the company.

A. after

B. before

C. when

D. since

答案：

A. after

B. before

C. when

D. since

解析：选D。考查状语从句。句意: ——你们彼此认识很久了吗? ——不是很久, 自从我们开始在这个公司里上班。结合上面的现在完成时态和句意, 应该使用since, 表示“从……起到现在”。