on grounds of （高考短语）
✅ 音标：/ɒn ɡraʊndz ɒv/
含义：以……为由；基于……（理由）
= on the grounds of（更标准，常省略the）
注意：grounds 永远复数！不是 ground。
ground 单数：地面；grounds 复数：理由、依据
句型
on (the) grounds of + 名词 / 名词短语
（后面不能直接加句子；加句子要用 on (the) grounds that + 从句）
例句1（你原题）
Employers cannot discriminate on grounds of age.
雇主不得以年龄为由歧视（他人）。
例句2
He refused the offer on the grounds of ill health.
他以健康不佳为由拒绝了这份邀约。
两种结构区分（考点）
1. on (the) grounds of + 名词
She was dismissed on grounds of laziness.
她因懒惰被解雇。
2. on (the) grounds that + 完整句子（that引导同位语从句）
She was dismissed on the grounds that she was lazy.
她被解雇，理由是她很懒惰。
同义替换（写作可用）
– because of +名词
– on account of +名词
– by virtue of （高级：凭借，由于）
易混提醒
❌ on ground of（错误，ground不能单数）
✅ on grounds of / on the grounds of
拓展短语
– have good grounds for sth 有充分理由做某事
There are good grounds for suspicion. 有充分怀疑的依据。