招标投标是合同的( ),它对合同的整个生命期有根本性的影响。
A.形成阶段
B.发展阶段
C.过渡阶段
D.实施阶段
参考答案:A
用适当的介词填空。
1. Liu Hang sits _______ the right side of the classroom. Li Gang sits in the front.
Zhang Xia sits next _______ him.
2. —Do you sit _______ the center of the classroom?
—No, I sit on Meimei's right. We sit _______ the front now.
3. Look _______ the picture. There is a pig _______ it.
4. Can you see the blackboard _______ the wall?
My teacher is drawing a tree _______ it.
5. There are some public phones _______ the street.
6. You can see the post office _______ the corner of the street.
7. There is a bird _______ the sky (天空).
8. My mother gets home _______ 6 o'clock every afternoon.
咽鼓管具有什么功能?