可以传播肠道疾病的是()
A.马
B.牛
C.苍蝇
D.蟑螂
参考答案:C, D
By the time you have finished this book, your meal ______ cold.
A.gets
B.has got
C.will get
D.is getting
钠石灰在吸收二氧化碳时不会产生()
A.热
B.水
C.碳酸钙
D.酸性物质
E.与氧化亚氮接触产生有毒物质