完成句子。

1. We are visiting the museum _______(后天).

2. We have to do a lot of homework ________(在平时).

3. I have a lot of housework to do_______(在周末).

4. —What are you doing _______(这个周末)?

    —I am visiting my grandparents.

绝缘介质劣化与老化的关系是（）

A.老化包含劣化

B.老化是可逆的，劣化不可逆

C.劣化、老化均可逆

D.劣化包含老化，老化不可逆