"Right" is an adverb that makes something more intense or immediate. Where are my keys? They're right there! (In front of me, very close) When you come to my house? I will be there right away! (very soon) I threw the computer right out the window! (it means the same thing, but it is more vivid and conversational, like a story) For American English, most of the time "right" appears in fixed expressions like "right here," "right now," "right away." In British English and in some American dialects people use it more like the word "very," but it's not common where I live. (near Chicago) Does that help?

Such a good question! I will try to answer. "Do/does/did" doesn't really have its own meaning here. It is more of a connecting word. However, it does tell you when something happens (present or past) and how many people are acting (singular or plural). Some examples: Not until he was sure everything was all right did the doctor leave the patient. (past tense, telling a story) Not until he is sure everything is all right does the doctor leave the patient. (present tense, or describing what usually happens every day) Not until they are sure everything is all right do the doctors leave the patient. (present tense, plural) "Until" is a preposition. "Not" modifies "until" - it negates it. (Just like 不／没）It's just like if someone says : "Where are my keys?" And you say "Not here." ("Here" is also a preposition) Someone can say, "When is the party?" And you can say "Not until 5PM." Does that help? 加油 ：）