问题
选择题
--Spacecraft "Discovery" has failed in the course of launch.
--_____? They have been preparing for the test.
A．How come?
B．When
C．What for
D．Why not
答案
答案：A
考查交际用语。A怎么会？为什么会这样？C为了什么？D为什么不？句意：—发现号在发射过程中失败了。—怎么会？他们一直在准备测试。