Complete the sentences with the proper forms of the words in the box.

contrast，protect ，preserve ，balance，proposal，likely，contribute ，conduct ，donate ，prevent

（1）How do they

preserve

preserve

food？
（2）Are you for or against his

proposal

proposal

？
（3）But if you do this，the friendship will

likely

likely

die.
（4）She made the

contrast

contrast

of this picture with that one.
（5）What we could do is to

donate

donate

some money for them.
（6）Your value is not what you possess，but what you

contribute

contribute

.
（7）Now we have a

balance

balance

of males and females in one class.
（8）We can do nothing to

prevent

prevent

this disease （from） spreading.
（9）We

conducted

conducted

an investigation into the issue，but we got no result.
（10）What do you think we have to lose if we fail to

protect

protect

our cultural heritage？