英语六级攻克阅读关键句284. Treatments for chronic conditions can eas
284. Treatments for chronic conditions can easily top $2,000 a month—no wonder that one in four Americans can't afford to fill their prescriptions.
译文 慢性疾病每个月的治疗花销很容易达到2000美元——难怪有四分之一的美国人都治不起病。
点睛 本句的主干是Treatments...can...top $2,000...，破折号后的内容则是对主句进行补充说明。one in four意为“四分之一”。
top在句中作动词，意为“达到，超过”，此外还含有“给……加顶；给……盖盖子”之意。如：
The workers are going to top the building tomorrow. 工人们打算明天给建筑封顶。
考点归纳 top作名词时，相关的短语很常见。如：
from top to bottom / from top to toe意为“从上到下，从头到脚；完全地”。如：
I know marketing from top to bottom. 我对市场营销了如指掌。
The stranger eyed me from top to toe. 陌生人从头到脚地打量着我。
from the top意为“从头，从开始”。如：
The guitar player replayed the song from the top. 吉他手把这首歌从头开始又弹了一遍。
get on top of表示因无能为力而使（某人）感到挫败和沮丧。如：
I don't want these boring things to get on top of you. 我可不想让这些烦人的事情缠住你。
on top of意为“在……之上；除……之外”。如：
Five people were crushed when the building collapsed on top of them. 那座大楼倒塌时把下面的五个人砸死了。
On top of borrowing a large amount of money, he asked us to lend him our car. 他向我们借了一大笔钱，此外还向我们借汽车。
on top of the world本义指“在世界的顶端”，引申义为“幸福到极点，兴高采烈”。如：
I was on top of the world when Mike proposed to me. 当迈克向我求婚时，我感到幸福极了。
