公元的英文：
A.D.
Christian era

Buddhism was introduced into China about A. D. 67.
佛教是在公元六十七年传入中国的。

"The first abbey was Monte Cassino in Italy, founded in 529 by St. Benedict of Nursia."
最早的大修道院位于意大利的卡西诺山，公元529年由努西亚的圣本笃创建。

West Saxon king(802 - 839)who became the first overlord of all the English peoples(829.
埃格伯特西撒克逊国王(802－839年)，公元829年成为英国人民的第一任君主

476aD saw the ruin of Roman Empire.
公元四七六年罗马帝国灭亡。

The Christian Era ;the period of history from the birth of Christ to the present day
基督纪元;公元.

The Christian era is counted from the birth of Christ.
公元是从基督的生年算起的。

born circa 1600
大约生于公元一千六百年。

St Pancras was martyred in 304 AD.
圣潘克拉斯于公元304年殉道。

Historians refer the fall of Rome to 410 A. D.
历史学家认为罗马衰落是在公元410年。

By the middle of the eighth century a.D., Tang power had ebbed.
公元8世纪中期，唐朝势力开始衰落。

Christmas is an important feast for Christians.
圣诞节是基督徒的重要节日。

I believe in Christianity.
我信仰基督教 。

The book was not intended to be an attack on Christianity.
这本书的本意不是攻击基督教的。

Christians go to church on Sundays.
基督教徒每个星期日到教堂去做礼拜。

He is an apostate from Christianity.
他是一个基督教的背信者。

We live in an era of rationality.
我们生活在理性的时代。

A new era is dawning.
一个新的时代开始出现了。

It's the end of an era.
这是一个时代的终结。

He was untimely born in this era.
他不逢时地生在这个时代。

He is the preeminent tenor of the modern era.
“他是现代杰出的男高音”