请问这句“I had to go to see the dentist”是过去时吗?如果是的话为什么后面的动词没有用过去

I often see my uncle go to the dentist.这句话对不对? go要用goes吗? 去看牙医不应该表示成go to see the dentist吗而为什么go to the dentist也有却看牙医的 if i had…i would 的后面加动词是原形 还是 过去分词? see a dentist是否等于 go to the dentist 新概念3册的,in response to renewed pleading.为什么To后面是过去时啊 I want to see the dentist.这里的to是什么意思,为什么要加,理由是什么? chat的过去非词是什么?如果用"to be ……"形式的话,一般是用过去时呢,还是有过去非词呀? i want to see the dentist I want to see the dentist,please. Kay has to go to see the dentist on Monday.(对划线部分提问）划线部分是go 一个英语问题teach sb to do sth如果句子是过去时,teach要改成过去式,后面的 动词（do） 要不要也 go to the dentist