38 Topaz Topaz is a hard, transparent mineral. It is a compound of aluminum, silica, and fluorine. Gem topaz is valuable. Jewelers call this variety of the stone precious topaz. The best-known precious topaz gems range in color from rich yellow to l

发表于:2018-12-08 / 阅读(358) / 评论(0) 分类 新概念优美背诵短文50篇

Topaz is a hard, transparent mineral. It is a compound of aluminum, silica, and fluorine. Gem topaz is valuable. Jewelers call this variety of the stone

发表于:2018-12-15 / 阅读(187) / 评论(0) 分类 新东方背诵文选

Topaz is a hard, transparent mineral. It is a compound of aluminum, silica, and fluorine. Gem topaz is valuable. Jewelers call this variety of the stone precious topaz. The best-known precious topaz gems range in color from rich yellow to light brown

发表于:2018-12-30 / 阅读(106) / 评论(0) 分类 考研背诵50篇

Topaz Topaz is a hard, transparent mineral. It is a compound of aluminum, silica, and fluorine. Gem topaz is valuable. Jewelers call this variety of the stone precious topaz. The best-known precious topaz gems range in color from rich yellow to light

发表于:2019-02-25 / 阅读(85) / 评论(0) 分类 双语有声阅读