Reading 1

3. to combine things to make them stronger or more effective
6. to protect something and use it carefully so it is not wasted or lost
7. no longer existing; when all members of a species have died
8. emphasize the importance of
10. the state of being easily hurt, harmed, or affected by something
12. a South American plant with large roots, or a type of flour made from these roots
14. the need to act quickly because something is important or serious
15. extremely important or necessary
16. a second plan you use if your first plan does not work

1. someone who is very interested in and enthusiastic about a particular subject
2. completely destroy a building, especially in order to use the land for something else
4. a confused mixture of different things
5. relating to genes and how traits are passed from parents to children
9. be strong enough, or not be changed by something, or to oppose a person or thing successfully
11. the main stem of a plant, or the narrow stem that joins leaves, flowers, or fruit to the main stem of a plant (plant part)
13. the gradual wearing away of land, soil, or rock by water, wind, or other natural forces