磷化处理时一次性粉末涂装所必须的工序，磷化膜的厚度应保持在（）g/m2以下。
A. 1
B. 3
C. 5
D. 7
参考答案：B
In many countries in the world, breakfast is a snack ______ a meal, but the traditional English breakfast is a full meal.
A．less than
B．more than
C．other than
D．rather than
