题目

请认真阅读下列各个小题，并根据上下文语境和所给首字母的提示，写出下列各句空格中的单词，注意保持语义和形式的一致。请将答案的完整形式写在答题卡上相应题号的横线上。【1】— Why have you been so restless these days?— Air tickets are in shortage. We are struggling to get seats on a plane b____for Mexico.【2】— Susan, do you know the meaning of “Brexit”?— Yes. It refers to Britain exiting from the EU, namely, the s ____ from EU.【3】— Have you heard of the famous translator Xu Yuanchong, who is still dev分解因式：x2+6x+9=　 　．