根据括号内的汉语提示完成句子。
1. We aim to _______ (提供) them with nice homes.
2. People have come to realize the _______ (重要) of protecting environment.
3. With the increase in population and the _______ (发展) of industry, litter is everywhere.
4. I often eat fresh fruit and vegetables _______ (代替) of chips and chocolate.
5. I think it is important to master computer _______ (技术) now.
6. I can't go shopping in a big store _______ (除非) I travel for a couple of hours.
