[解析]
(1)B.细节理解题。根据第二段When the emperor decided that single men could become better soldiers than those with wives,he didn't allow marriage.当皇帝决定单身男人可以成为比有妻子的男人更好的士兵时,他不允许结婚。可知,罗马皇帝认为单身男人比有妻子的男人更适合当兵打仗,于是他下令禁止结婚。故选B。
(2)C.细节理解题。根据第三段But Valentine continued to perform marriage ceremonies for young lovers in secret.When his actions were discovered,the emperor sentenced him to death.但瓦伦丁继续秘密地为年轻情侣举行婚礼。当他的行为被发现时,皇帝判处他死刑。可知,瓦伦丁没有遵守皇帝的命令,于是被捕入狱,故选C。
(3)D.段落大意题。根据最后一段Nowadays,Valentine's Day is also popular among Chinese young people.如今,情人节在中国年轻人中也很流行。可知,情人节现在在中国年轻人当中非常的普及。故选D。
(4)A.标题判断题。根据第一段February has long been a month of romance.With the sweet smell of roses in the air,romantic films hit cinemas and love stories fill newspapers and magazines.二月一直是浪漫的月份。随着空气中玫瑰的芬芳,浪漫电影在电影院上映,爱情故事充斥着报纸和杂志。可知,文章主要帮助我们了解情人节的历史,故用标题Valentine's Day(情人节),最合适,故选A。