It's difficult enough without muddying the issue with religion.
即使不和宗教搅在一起，这个问题也已够难的了。
《柯林斯英汉双解大词典》
2
Muddying the whole issue has been the parallel use of “core interests” advanced by Mr.Dai.
戴先生首先对“核心利益”这个词的平行使用使得这整个问题变得混乱起来。
3
For example, groups of baboons that usually live apart as apparently separate species sometimes aggregate and interbreed, muddying their classification.