用适当的介词填空，如不需填则画“／” 。

1.  Will you have a chemistry lesson  _______ next term?

2. What do you usually do _______- weekends?

3.  I have too much homework _______this weekend.

4.  We are leaving ________ the 15th.

5.  Christmas Day is _______ December.

简述脊髓损伤患者行走训练前应评定的内容。