全球性环境污染问题指的是[ ]
A.水土流失、沙尘暴、水体富营养化
B.砍伐森林、围湖造田、水华
C.酸雨、温室效应、臭氧层破坏
D.过多使用农药、使用含磷洗衣粉
答案:C
Yesterday morning ,Jim hurried to the station .He was very angry __ the train had just left.[ ]
A. and
B. so
C. because
D. so that
绞窄性斜疝局部有感染者,应选的合理手术方式是
A.单纯疝囊高位结扎术B.Ferguson法C.McVay法D. Bassini法