1 . ___________（convince） that the government can lead them out of the financial crisis, people are optimistic about the future of the country.

2 . ___________(convince) that the government can lead them out of the financial crisis, people are optimistic about the future of the country. (所给词的适当形式填空)

3 . Columbus called the natives living on the islands Indians because he ________ (convince) that he was in the East Indies. （所给词的适当形式填空）

4 . We were finally able to make the customers ____________ (convince) of the quality of the refrigerator.