厌氧反应过程可分为(),(),(),(),四个阶段。
参考答案:水解阶段;发酵阶段;产酸阶段;产甲烷阶段
As soon as she entered the room, the girl caught sight of the flowers ________ by her mother.
A.buying
B.being bought
C.were bought
D.bought
对于原发性周围型肺癌,首选的治疗方法是
A.中医中药治疗
B.免疫治疗
C.放射治疗
D.化学治疗
E.手术治疗