suddenly是副詞,表示“突然地”,用來修飾動詞、形容詞、副詞,一般在形容詞後-ly。如:He suddenly stopped his work and went out.句中的suddenly修飾動詞stop,是副飼。如:beautifully,certainly,happily,absolutely等。但並不是所有-ly結尾的都是副詞。如:friendly(友好的),lovely(可愛的),likely(可能的),這幾個都是形容詞。