根据句意和首字母提示完成单词。

1．The students s         the classroom half an hour ago, so it is very clean now．

2．Betty is a v    ．She practices playing the violin every day．

3．We never forget our f       of twenty years between us．

4．Thanks a lot for the i        ．But I'm sorry I can't visit next week．

5．Be careful when you c       the road．