催化剂不具有选择性。
参考答案:错
The apples are delicious. I'd like to have third one because second one is rather too small and
I had little food at lunch. [ ]
A. a; a; the
B. the; the; the
C. a; the; /
D. a; a; /
明清时期,随着商品经济的发展,江南一些工商业城市的丝织业中出现了“机户出资,机工出力”、“计日受值”的现象,它反映了当时世界历史的发展趋势,该现象最有可能出现在()
A.外商企业
B.民间手工业
C.家庭手工业
D.官营手工业