题目

Judging from his (puzzle) look, we know that the boy is faced with a tough situation. 答案：【1】puzzled炎热的夏天食品容易腐败主要是由食品中的    和真菌引起的，它们从食品中获得    作为营养，大量生长和繁殖，导致食品的腐烂．