产品设计
参考答案：
将顾客的需求或新产品构思变为具体产品的一个实现过程。
用所给词的正确形式填空。
1. Let's (put) the letter in the envelope.
2. They are (fly) kites in the park.
3. Danny is (write) a letter for his friends.
4. She (want) to go shopping.
5. They (have) fun yesterday.
塔台、进近、区域管制室管制席位应当安排（）以上持有执照的管制员值勤。
A.2名
B.3名
C.2名（含）
D.4名
