选用方框内的单词，并在答题卡标有题号的横线上，写出空缺处各单词的正确形式。每空只写一词。

After three years of    ▲ , she left her husband at last.
Mobile phones are    ▲  used around the world now.
We should try our best to help the    ▲  people.
Computers are really one of the greatest    ▲ .
 ▲  exchange is a way of building a bridge between nations.