中文原文：

对英语，我只懂一点皮毛。

错误译文：

I only have a smattering of the knowledge about English.

正确译文：

I only have a smattering of English.

翻译加油站：

smattering 在这里的意思是limited knowledge 或superficial knowledge，即“有限知识”或“表面知识”。初学者爱说My English is poor，以示自谦，其实不合英语习惯。不如说I only have a smattering of English更为地道。
a smattering of 后面一般跟一种语言。例如：我在巴黎逗留期间学了一点法语。I picked up a smattering of French during my stay in Paris.但是，a smattering of 还有a small number of 或a small amount of的意思，前者跟可数名词，后者跟不可数名词，具有“少量”或“一点儿”的意思。例如：她仅会一点儿英语单词。She knows only a smattering of English words.

“懂得一点儿”和“懂点皮毛”，还可以译为to know a little about sth。“一知半解”可以译为to have a superficial knowledge of sth, to have a scanty knowledge of sth。例如：他们对公司如何运作仅有一知半解。They only have a scanty knowledge about how a company operates.

“所知甚少”可以用to know very little, not to know much, to have little knowledge等方式表示。例如：说老实话，我对西方文化所知甚少。To be honest, I knew very little about Western culture.

“一无所知”或“全然无知” 可以译为 to be absolutely/completely/ quite/totally ignorant about/of sth 或to be completely in the dark。例如：这两个人从来没有互相见过面，而且对互相的工作全然无知。The two people never saw each other, and they were completely ignorant of the other's work.

“被蒙在鼓里”可以译为to be kept completely in the dark。例如：经理计划将公司出售，但是股东们被蒙在鼓里。The manager planned to sell the company, but the shareholders were kept completely in the dark．