下面（）叙述不是影响齿轮传动精度的因素。
A、齿形精度
B、齿轮加工精度
C、齿轮的精度等级
D、齿轮带的接触班点要求
参考答案：A
根据句意及括号内所给英文提示，完成句子。
1. The woman ________(drive) often drives her car to her son’s school.
2. The teacher comes from Canada. He ________(teach) us English.
3. There are twelve ________(people) in his family.
4. Please make _________(you) at home, kids.
5. There are two new __________(factory) and only one tree in the picture.
字符函数String(2，"abcdef")返回的值是 ______。
A．"aa"
B．"AA"
C．"ab"
D．"AB"
