B-ISDN的协议参考模型每个面又分为3层，即（ ）。

A．物理层、ATM层和删适配层

B．物理层、ATM层和拆装层

C．物理层、ATM尾和会聚层

D．物理层、ATM层和公共会聚层

翻译下列词组。

1. 根本不                                                 2. 犯错                                                                     

3. 随后                                                     4. 害怕去做                                              

5. 取笑(某人)                                           6. 做笔记                                              

7. 说本族语的人                                      8. 结束（做某事）                                      

9. 学习语法                                            10.  首先