完成句子（每小题2分，共10分）
根据所给汉语意思，用单词或短语完成下列英语句子。
小孩子不允许和大人顶嘴。
Little children should not ______________________talk back to their parents.
据说数字十三在西方国家是不吉利数字。
_________________thirteen is an unlucky number in many Western countries.
两个说法都正确，但是第一个听起来没那么礼貌。
Both are correct, but the first one sounds ________          .
茶是在大约七世纪被引进韩国和日本。
Tea was brought to Korea and Japan about _______ century.
我很害羞不敢在公共场合说话。
I am too shy to speak ______________.