1 . Failure can make positive ________(贡献)to your life once you learn to make good use of it. （根据汉语提示单词拼写）

2 . He made a big ________(贡献) to setting up the hospital. （根据汉语提示单词拼写）

3 . He is a hero who made great________ (贡献) to the development of our country. (根据汉语提示单词拼写)

4 . Studies show that insects could make valuable ________(贡献) to the food system. (根据汉语提示单词拼写）