题目

 When she came into the room and saw that her child was nowhere _____, she became very anxious.    A. to be seen    B. to see               C. seeing               D. being seen 答案： A。nowhere to be seen/found意为“任何地方都找不到或看不见”。句意：当她进屋一看，发现孩子不见了，变得非常着急。食品添加剂溴酸钾(KBrO3)会致癌，其中溴元素(Br)的化合价为　　 (　　) A.+1　　B.+3　　C.+5　　D.无法确定