To complete the sentence "You know that you ____ it before tomorrow," we need to choose a verb phrase that correctly conveys an obligation or probability in this context. Let's analyze the options:
1. Might do: This implies a possibility of doing something but with uncertainty. Therefore, it doesn't fit well after "you know" because knowing implies certainty.
2. Ought to do: This implies a recommendation or obligation. "You know that you ought to do it before tomorrow" suggests a sense of necessity or duty that aligns well with "you know."
3. Like to do: This implies a preference, habit, or enjoyment, which doesn't necessarily align with the sense of certainty or requirement implied by "you know."
4. May do: This suggests permission or possibility, which again does not fit well after "you know" due to the lack of certainty or obligation.
Therefore, the best option to complete the sentence, considering the context of certainty or a strong recommendation, is "ought to do." This reflects that there is a known obligation to complete the task before tomorrow.