knowledge
1.复数形式knowledges现在很少用,如a man of many small knowledges。但前面可以用a。例如:He has a perfect knowledge of English. 和I have only a slight knowledge of Shanghai.
2.knowledge of English(或Chinese等)不可改作knowledge in English(或Chinese等),也不可改作English(或Chinese等)knowledge。
3.knowledge后面可以接以that引导的从句。例如:He was surprised at the knowledge that his wife was dead.
4.knowledge后面有时接以how,what等词引导的从句。例如:The boy found himself in a boat without the slightest knowledge how he had got there.
5.to my knowledge和within my knowledge意思略有不同。例如:
They have met three times, to my knowledge. (据我所知,他们会见过三次[不是三次以上或以下]。)
They have met three times within my knowledge. (据我已知,他们只会见过三次[不是三次以上]。)
6.关于common knowledge,参见common 2