1.If you decide to take _____ train to Beijing, you may have quite a pleasant journey, but make sure you get _____ fast one.
A. a ; a B. the ; a C. /; a D. a; /
2.Astronauts came back from a 68-hour flight, ________ included a 20 –minute space walk .
A. which B. in which C. on which D. where
