问一下eat,eats,eating的用法.如果是在疑问句,否定句中是不是要用eat这个原型?比如

eat,watch是原形,用在助动词后,如：
Does he eat meat?
He doesn't watch TV on work days.
eats,watches是三单,用于第三人称单数,如：
He usually eats meat for lunch.
He watches TV only at weekends.
eating,watching是现在分词,一般用于进行时,如：
He's eating dinner.
He's watching TV.