加:3 plus 6 is 9. 3 and 6 equals 9. 3 and 6 is equal to 9. 3 added to 6 is 9. 减:6 minus 3 is 3. 乘:3 times 6 is 18. 3 multiplied by 6 is 18. 除:6 devided by 3 is 2. 分数:four fifths 年代:nineteen eighty-seven 日期:12月9是December ninth 9月12是September twelfth 我是高中生、相信我请给分!多谢!