一)内容提示：

优点：1). 足不出户，节约时间，不会拥挤劳累

2). 价格通常比较便宜

3). 可供选择的范围广，品种多

缺点：1). 只看到图片，看不到商品本身

2). 容易购买大量不需要的东西，造成浪费

二)要求：

1). 所表述内容必须包含提示中所有方面。

    With the development of the Internet, many people are used to shopping online.

分解因式：ab²﹣9a=　___　．

增加：在缺词处加一个漏字符号（∧），并在其下面写出该加的词。

删除：把多余的词用斜线（＼）划掉。

修改：在错的词下画一横线，并在该词下面写出修改后的词。

注意：1.每处错误及其修改均仅限一词。2.只允许修改10处，多者（从第11处起）不计分。

    My friend Lin Tao was born in Liaoning Province to the northeast of China. He met with a traffic accident when he was younger. As a result, he lost one of his legs. Although he suffered a great deal, he never loses his heart. Lin Tao has been published a book. He enjoys playing his guitar and listen to music. He does excellent job in school. But he is always ready to help those in trouble. He wins the respects of his classmates and his teachers.

    In my opinion, Lin Tao is extreme brave and he sets a good example to we all.

城市发展后期．城市社会经济表现为(    )