阅读下列短文，根据短文内容填空。在未给提示词的空白处仅填写一个适当的词，在给出提示词的空白处用括号内所给词的正确形式填空。
These pioneers of the 20th century were all dedicated to improving the quality of human life on earth, but sometimes breakthrough discoveries that 【小题1】 (affect) our lives today happened by mistake! For example, we are all grateful for the handy microware oven that allows us 【小题2】 ( prepare )meals in minutes and we have Percy Spencer to thank. This inventor, with 120 patents to his name, discovered microwaves when he was experimenting with radars and noticed a chocolate 【小题3】 (melt) in his pocket.
