请列举三种影响卫生服务需要与利用的因素：______、______、______。
参考答案：人口数量及年龄性别构成 社会经济因素 医疗保健制度
The students busily when Miss Brown went to get the book she in the office.
A．were writing; left
B．wrote; had left
C．had written; left
D．were writing; had left
叶天士认为，风温的发生是因为（）
A.外感风温时毒
B.温风过暖，感其气者
C.春月受风，其气已温
D.感受春季温热病邪
E.感受风邪
