Here are some suggestions to fill in the blanks:

1. Some (environment) **organizations** are trying to clean up our beach.
2. These laws may not provide enough (protect) **protection** for some endangered species.
3. This group of chemicals is known to be (harm) **harmful** to people with asthma.
4. Both children escaped (harm) **harmlessly** from the burning building.
5. Safety glass will break into relatively (harm) **harmless** pieces when it is hit hard.
6. He is talking to some volunteer (conserve) **conservers**.
7. Older people tend to be more (conserve) **conservative** and a bit suspicious of anything new.
8. To (conserve) **conserve** electricity, we are cutting down on our heating.
9. Please! Listen to the lecture (care) **carefully**.
10. An accident happened because of driving (care) **carelessness**.

Feel free to adjust these based on the context!