— Spacecraft “Discovery” has failed in t
问题:
— Spacecraft “Discovery” has failed in the course of launch.
— _______? They have been preparing for the test.
A.How come
B.When
C.How
D.Why not
— Spacecraft “Discovery” has failed in the course of launch.
— _______? They have been preparing for the test.
A.How come
B.When
C.How
D.Why not