Mukai Chiaki, the first female Japanese astronaut, ……….. 15 days aboard the space shuttle Columbia in space before it …….. to the Earth on July 23,1994.
A. spent - had returned
B. had spent - returned
C. was spending - was returning
D. spent - was returning
* Đáp án
* Hướng dẫn giải
Đáp án: B
Giải thích: Hành động xảy ra trước một hành động trong quá khứ