“一知半解”常见的英文表达有 “have a smattering of knowledge”、“have a superficial/cursory knowledge” 或 “know a little about something without thorough understanding”。以下为具体分析：
1、 “have a smattering of knowledge”
“smattering” 意为“少量；一知半解”，此表达强调对某事物只有零星、浅薄的了解。
例句：He has a smattering of knowledge about ancient history, but he can't discuss it in depth.（他对古代历史一知半解，无法深入讨论。）
2、 “have a superficial/cursory knowledge”
“superficial” 意为“表面的；肤浅的”，“cursory” 意为“草率的；粗略的”，二者均表示对事物的了解停留在表面，缺乏深度。
例句：She has a superficial knowledge of physics, which is not enough for her research.（她对物理只有一知半解，不足以支持她的研究。）
3、 “know a little about something without thorough understanding”
此表达更直白地说明了“对某事物了解一点，但并不透彻”的含义。
例句：I know a little about painting, but I'm far from an expert.（我对绘画一知半解，远非专家。）