用方框中所给单词的适当形式填空，每词仅用一次。
Larry has put on too much weight because of his __________ diet.
Jack finds it difficult to pronounce some English words __________.
I could hardly believe she had made a video about water pollution all by__________.
If we teenagers offer to do more volunteer work, the future of the world __________ much brighter.
Our knowledge of the universe __________ so much in the past hundreds of years with the development of modern science and technology.