减少氧化加热的目的是（）。
A.节约燃料
B.保护被加热金属
C.防止冒黑烟
D.防止污染
参考答案：B
He ______ this dictionary for 5 years. He ______ it in 2004. [ ]
A. has bought; bought
B. bought; bought
C. has kept; has bought
D. has had; bought
现代国际商务礼仪带有很浓厚的欧美文化的特点。( )
