第 45 课: 各种运算：加，减，乘，除-3

Three plus four is seven. 三加四等于七

Three plus five is eight. 三加五等于八

Six minus two is four. 六减二等于四

Six minus four is two. 六减四等于二

Six plus five is eleven. 六加五等于十一

Six plus six is twelve. 六加六等于十二

Four plus three equals seven. 四加三等于七

Four plus five equals nine. 四加五等于九