13．A new simplified desktop computer has been developed for people aged over 60 to make them _________with PC and the Internet.

Are Jiangsu and Zhejiang famous for silk— I think so. I know, more than half of the silk in China is produced in Jiangsu and Zhejiang.

a long journey they arrived______ in Naples, where they stopped to trade with the local people.

Collecting stamps as a hobby___________ increasingly popular during the past fifty years.

_________do you write a letter to your father— I seldom or never do that now. Instead, I call or e-mail him almost every day.