这四个词作为接尾词接在动词的连用形后都表示“难…”的意思。但它们四个之间在语感上是有区别的,不能随便互相顶替换用。另外,前三者接在动词连用形后构成形容词,按形容词活用;而 These four words as the tail word after the verb conjunctive form all means “hard ...” meaning. However, there are differences between the four in their sense of language, and they can not be used interchangeably with each other. In addition, the first three connected verbs form the adjective, according to the adjectives;