he usually has dinner at eight变否定

变为否定是非常简单的。

首先，我们找到其中的动词。一句话中只有一个谓语动词。he usually has dinner at eight中的谓语动词是has，当我们把它变成否定式的时候，要在谓语动词前面加上does，因为he是第三人称。

所以改为否定是he usually doesn't has dinner at eight

he usually has dinner at eight变否定

答案应该是：He doesn't usually have dinner at eight.