第252句：

This law was declared unconstitutional by the Supreme Court on the grounds that general taxes were being collected to pay one special group of people.
最高法院宣布這項法律違反了憲法，因為普通稅收都被收集起來，付給了某一特定的人群。

六級詞匯講解:

本句的主干是This law was declared unconstitutional...。on the grounds引導原因狀語從句。
unconstitutional為constitutional的反義詞，意為“違反憲法的；非立憲的”。the Supreme Court指“最高法院”。on the grounds that意為“因為；以……為理由”。

英語六級考點歸納
與ground相關的短語及用法如下：
from the ground up意為“從頭開始”。如：
Don't give up. You can do it from the ground up.
別放棄，你可以從頭開始做起。
break ground意為“開辟道路；改革”。如：
The new country will break ground on all aspects.
這個新國家將從各方面進行改革。
lose ground意為“撤退；被某人／某事物逐漸趕上”。如：
The leader was losing ground as other runners accelerated.
領先者在另lJ的賽跑者加速時，逐漸失去優勢。