1. The student (who / whom / x) was selected to join the space program is my brother’s friend
2. They showed me the place (when / which /x) the spaceship landed last week.
3. David introduced me to the woman (whom / whose / x) husband is working for NASA.
4. The astronomer (which / whose / x) you want to meet is going to present a paper at the conference next Friday.
5. The twenty-ninth of May is the day (that/which /x) our astronauts will be returning home.
6. The man with (who / whom/x) Mr. Khoa is talking has flown into space three times.
7. The satellite (where / that / x) was launched into space yesterday belongs to Viet Nam.
8. The space age began in 1957 (when / which/x) the Soviet Union launched Sputnik 1, the world’s first man-made satellite.
9. An astronaut is a person (whom / that /x) travels in a spacecraft into outer space.
10. The book (who / where /x) I’m reading is about the history of space exploration.