Here are the suitable prepositions for each blank:

1. Will we pick **up** litter around our school this Sunday?
2. Our parents will help us whenever we are **in** need.
3. He was kind **to** sad and disappointed about his health.
4. We provided the street children **with** warm clothes.
5. This park is a popular place **for** residents in my neighbourhood.
6. They can enjoy water sports, or simply lie **on** the beach.
7. We've asked people to donate books and clothes **for** the children.
8. Could you please tell us **about** the community service?
9. Her collection has dolls from all **over** the world.
10. Eric wants to climb mountains **in** other countries.

For the verb forms:

1. They **gave** warm clothes to homeless people last week.
2. We **will find** great ways to change the world.