Sure, here are the answers to your questions:
1. I would never **presume** to enter your room without asking you first!
2. I got out of the car and ran inside to escape from the **torrents** of rain.
3. Would you **object** to changing our dinner plans from Wednesday to Thursday night?
4. There was a very **grave** mood in the room after the sad announcement.
The word **presume** means to assume something without evidence. In this sentence, the speaker is saying that they would never assume that they have permission to enter someone else's room without asking first.
The word **torrents** means a large amount of water flowing rapidly. In this sentence, the speaker is describing the heavy rain that they were running from.
The word **object** means to express opposition to something. In this sentence, the speaker is asking if the other person would have any problems with changing their dinner plans.
The word **grave** means serious or solemn. In this sentence, the speaker is describing the somber mood that was created by the sad announcement.
I hope this helps! Let me know if you have any other questions.