患儿女，3岁，近半年出现点头、跌倒及强直性发作，伴智力运动发育倒退，其脑电图改变可能为（）

A.爆发-抑制脑电图

B.全脑3Hz棘-慢复合波

C.高幅失律

D.全脑慢波背景上重叠1.5～2.5Hz棘-慢复合波

E.慢波睡眠期棘慢波持续发放

根据汉语意思，完成下列句子。

1. How far is it from your home to school?

                                                               (大约四公里).

2. How long does it take you to walk to school?

                                                             (二十分钟).

3. How do you go out for travelling?

                                                            (坐火车).

4. Where is the Peace Park?

                                                          (离学校十五英里).

5. Do all the students in America take the school bus to school?

    No, in America,                          (并非所有学生乘校车上学).