2、it goes without saying that… 不言而喻，…
3、it can be said with certainty that… 可以肯定地说……
4、as the proverb says， 正如谚语所说的，
5、it has to be noticed that… 它必须注意到，…
6、its generally recognized that… 它普遍认为…
7、its likely that … 这可能是因为…
8、its hardly that… 这是很难的……
9、its hardly too much to say that… 它几乎没有太多的说…
10、what calls for special attention is that…需要特别注意的是
11、theres no denying the fact that…毫无疑问，无可否认
12、nothing is more important than the fact that… 没有什么比这更重要的是…