The difference between "by then" and "until then" is that of continuity. "Until then" means that the thing will continuosly be done till "then" comes. For example, You go and rob …
By thenuntil then|Use "by" for positive verbs that express a punctual action that is not continuous (like leave, return, start, finish, turn in, pick up, inform, contact). Use "until" for …
Remember, " until " cannot be used followed by the future tense, all the others alternatives are suitable for until, past tense, past continuous, present tense, present …
It's a common misconception that "till" (or "til") is an informal, shortened version of "until." Actually, till came first (check a reliable dictionary). If you want to avoid …
up until thenIt means the timeframe before a specific deadline or point in time. For example: - The fighting began on the first of October. Up until then, the two countries were at peace. …
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