我们和那些政治家之间的关系很不稳固。There is an uneasy relationship between us and the politicians.这项研究犹如建在流沙之上，基础极不稳固。The research seemed founded on quicksand.这项和平条约建于不稳固的基础上.The peace treaty rests on shaky foundations....
We needed to do decimals to round up and round down numbers.我们得把小数四舍五入成整数。The students had a grasp of decimals, percentages and fractions.学生们掌握了小数、百分数和分数。T: Who can divide the repeating decimals into two groups? Why?师: 谁...