1UNIT SIX I HAVE FIFTY MARKERSLesson 21习题1、抄写下列单词blackboard seventy eightyninety hundred2、英汉互译blackboard_hundred_seventy_八十_三、补全对话A: Whats fifty plus two?B: 52.四、翻译下列句子1. Whats six plus twenty?_2.50+20=?_3. Do you know the missing number? _24. The missing number is twenty._参考答案:一、略二、1.黑板 2.一百 3 .七十 4. eighty三、Fifty two.四、1.六加二十等于多少? 2. Whats fifty plus twenty?3.你知道空缺的数字吗?4.空缺的数字是 20.