The expansion of desert like conditions into areas where they did not previously exist is called desertification.
问题描述：
The expansion of desert like conditions into areas where they did not previously exist is called desertification.
答
主要结构：The expansion of desert （主） is called desertification.沙漠的扩张就叫做沙漠化.like conditions into areas where they did not previously exist 此为插入语.like是指The expansion of desert (主...