因爲副詞是來修飾動詞。
She dances well.
她跳舞很好。
Some dancing would ginger up the party .跳跳舞就可以使聚會活躍起來。
Waves of heat danced above the engine hood .熱浪在引擎蓋的上方翻騰。
She danced the little child round the room .她逗得小孩滿屋蹦蹦跳跳。
Dancing has lost all its enchantment for her .她已完全失去跳舞的樂趣。
The boy was coerced into learning to dance .那男孩被強制去跳舞。
Dance 是動詞，副詞是來修飾動詞的，跳舞跳的好即good的副詞形式爲well所以後面加well爲dance well
