她收到一枚美丽的钻石戒指作为订婚礼物。

She received a beautiful ___diamond ring as an engagement gift.

他曾在南非的一座钻石矿工作。

He once worked in a South African ___diamond mine.

她发现自己的手指上戴着一枚惊艳的钻石戒指。

She discovered a stunning ___diamond ring on her finger.