can’t be overemphasized / can’t be emphasized too much

解析:本句考查的是"再……也不为过的"的说法。英语句型是:cannot + do sth. + too much 或 cannot over-do，如:He is so excellent that we cannot praise him too much.(他是这样的优秀，我们怎样称赞他都不过分。)cannot是否定，与too much 和 over-V.结构连用时强调肯定，表示"怎么……也不为过"。