第四组：选择to do；doing；done填空

4）I will never forget            （meet）him for the first time．He was a lovely little boy then．

3）I really appreciate          （have）time to relax myself on this lovely island．

2）The students are forbidden，unless they have special passes，        （stay）out after 11 pm．

1）I will not allow my son            （risk／take）mountaineering．It’s a dangerous sport．

第三组：选择to do或doing填空

3）The summit             （hold）next week in Shanghai is about the environmental protection．

2）The hotline           （put）into use in 2004 has given a lot of help to thousands of families．