第27题: [单项选择]For workers in small firms employment ________ are very rare, working hours are longer and safety records poor. A. guarantees B. reservations C. securities D. assumptions 参考答案:A 答案解析:[解析] 语义连贯题。所填词和employment搭配,并和working hours,safety records是并列关系,[A] guarantees“保障,保证”符合句意,所以[A]为答案。[
第28题: [多项选择]引起弥散量降低的有 A. 肺出血 B. 肺结核 C. 气胸 D. 肺间质纤维化 E. 红细胞增多症 参考答案:B,C,D