计算:6tan230°-cos30°·tan60°-2sin45°+cos60°。
解:原式=。
用“there be” 的正确形式填空。
1. ________________ some books on the desk.
2. ________________ some tea in the cup.
3. ________________ an orange and two apples on the table.
4. ________________ some sheep near the house.
5. ________________ any coffee in the cup?
Yes, ________________.
6. ________________ any trees in the picture?
No, ________________.
7. ________________ nothing in the bag.
8. ________________ a bird in the tree yesterday afternoon.
9. ________________ a little water in the glass.
10. ________________ some money in my pocket.
下列关于胸部边界的叙述错误的是()
A.下界相当于胸廓下口
B.胸部和上肢的界限是三角肌前缘
C.上界往后到第7颈椎棘突
D.上界是胸骨颈动脉切迹
E.上界沿锁骨到肩锁关节