请问 he feels ill 的feels 为什么要加-s?

请问 he feels ill 的feels 为什么要加-s? He says that he feels ill.为什么里面要加that He feels ___(terrible) ill. he feels _(terrible) ill. he feels ill这里的ill做什么成分 it feels like ,feel为什么要加s he feels ill怎么变问句 He feels ill 如何改一般疑问句 Tom is ill.He feels t_____ This kind of paper feels very soft 为什么feel要加s ? he feels ill的以how开头的特殊疑问句,一般疑问句,否定句 英语He feels ill 如何改特殊疑问句