There is a lack of knowledge about the tax system.
大家對稅制缺乏了解。
For years we had little knowledge of what life was like inside China.
以往很多年我們對于中國國內的生活情況所知甚少。
He never made a will, to the best of my knowledge.
據我所知，他從未立過遺囑。
She has acquired a good knowledge of English.
她英語已經學得很好。
Our knowledge of the disease has advanced considerably over recent years.
近年來我們對這種疾病的了解深入多了。