English is quite an easy language to be known. It is suggested to be perfect in the grammar to have grip and perfection about any language. Thus, every language has its grammar and rules for the same. English grammar contains verbs, nouns, pronouns, tenses, modals, synonyms, antonyms, homophones, and many more. The terms “Have to’ and “Had to” are part of models and do have the slightest difference between them.