腹腔穿刺液中有大量中性粒细胞,革兰阳性球菌。常见于()
A.原发性腹膜炎
B.胃、十二指肠穿孔
C.阑尾炎穿孔
D.肝脾破裂
E.出血坏死性胰腺炎
参考答案:A
Everyone knows that________ is dangerous to play with fire, but________ is difficult is to prevent children from playing with fire.
A.it; what
B.what; what
C.what; it
D.it; it
你选择测试方法的原则是什么?