Match these definitions to a word from C in the vocabulary section. Use a dictionary if necessary.

1. to keep delaying something that must be done 
2. to make something poisonous or less pure 
3. to throw out with force 
4. suddenly to increase a lot in number 
5. to sympathise with someone’s unhappiness 
6. to change from a liquid or soft state to a solid or hard state 
7. to produce young (formal) 
8. to chat (formal) 
9. to send out (a beam, noise, smell or gas) 
10. to encourage people to buy or use something