一个长方体的长6cm，宽4cm，高3cm，它的棱长和是______，表面积是__

下列句式间的转化是否你都掌握了？

1. It's time for lunch. (改为同义句)

    It's time _____ _____ lunch.

2. He does well in English. (改为同义句)

    He _____ _____ _____ English.

3. He has his lunch at school every day. (改为否定句)

    He _____ _____ his lunch at school every day.

4. He didn't go home because he went to the park. (就划线部分提问)

    _____ _____ he go home?

5. We go to see a film once a week. (就划线部分提问)

    _____ _____ do you go to see a film?

心下坚筑

当今以太网，经常采用双绞线或光缆，组建星型拓扑结构网络。交换型以太网逐渐替代共享型以太网，并使用（）以太网技术。

封寄

叙述并指出夹脊、内庭、神门的定位。