【单选题】According to the passage, as the nineteenth century progressed, the people of the United State ______.
A.
emigrated to other countries
B.
often settled in the West
C.
tended to change the place in which they lived
D.
had a higher rate of birth than ever before
【单选题】枯叶蝶腹面的色泽和形状极似枯叶 , 这是枯叶蝶的祖先 ( )
【单选题】吴女士,26岁,妊娠5个月。患支气管扩张症5年。今晨突然鲜血从口鼻涌出,随即烦躁不安,极度呼吸困难,唇指发绀。不宜选用的止血药为
【简答题】A.In the early nineth century. B.In the early twentieth century. C.In the late nineth century. D.In the mid-twentieth century.