简述脊索动物门的基本特征。
参考答案：
1）具有脊索
2）具有中空的背神经管
3）有咽鳃裂
It is said that people are ______ likely to tell lies over the phone as they are in emails. [ ]
A. as twice
B. twice as
C. twice more
D. twice than
什么是地方民族主义？
