问题
选择题
They were _______ busy ______ the project ______ the time.
A．too; to discuss; to forget
B．too; discussing; to forget
C．so; to discuss; that they forgot
D．so; discussing; that they forgot
答案
答案：D
题目分析：句意：他们太忙于讨论这个项目以至于忘记了时间。be busy doing sth 意为忙于做某事。so……that 如此……以至于……。故选D。
