**35. Why do climbers on Mt. Everest carry a bottle of oxygen?**
- A. The weather is cold.
- B. Climbing makes them tired.
- C. The air is very thin.
- D. They are thirsty.
**Answer: C. The air is very thin.**
**36. In line 5, people leave them behind, what does the word them refer to?**
- A. Tents
- B. Oxygen bottles
**Answer: B. Oxygen bottles**
### Make questions for the underlined words
**37. The Muong people often play flute, trumpet and gong.**
→ **What instruments do the Muong people often play?**
**38. The Viet is the largest ethnic group in Vietnam.**
→ **Which is the largest ethnic group in Vietnam?**
**39. The Muong live in mountainous areas with abundant land for growing wet rice.**
→ **Where do the Muong live with abundant land for growing wet rice?**
**40. They are harvesting their crops in the fields.**
→ **What are they doing in the fields?**
### Using the words given to write the meaningful sentences
**41. I visit/my neighbors/yesterday/no one/be/home.**
→ **I visited my neighbors yesterday, but no one was home.**
**42. You/like/cup/of/coffee/you/like/glass/of/water?**
→ **Would you like a cup of coffee or a glass of water?**
**43. Mr. Smith/seem/nice/man/he/be/selfish.**
→ **Mr. Smith seems to be a nice man, but he is selfish.**
**44. Ann/want/lose/weight/she/go/the/gym/regularly.**
→ **Ann wants to lose weight, so she goes to the gym regularly.**