算一算,填一填,你发现了什么?(仿练教材第63页第13题)
18+81=99 27+72=____ 36+____=____ ____+____=____
99-18=____ 99-27=____ 99-____=____ ____-____=____
— I saw Mr. Green at school this morning.
— No, it _____ him. He flew to Canada last week.
排列正确的是:( )
默写填空。