be up to

[Anonymous]

Hi,
Please check if these sentences are correct and natural?
1. He's very quiet; he must be up to something!
2. Why is he being so nice to me? He must be up to something!
3. I could tell by looking at him that he must be up to something.
4. He suddenly got a mischievous grin on his face, so I suspected he must be up to something.
5. Do you know anybody who had/bore a grudge against your father?
6. These are your father's last wishes/words/will.
7. According to (the provisions of) Mr. Pope's will, Miss Bridge shall/will be furnished (with) a stipend until she graduates from a college of her choice. After/Following that, she'll be provided (with) a trust, $25,000 a year for life.
Thanks a million.
Ann

[Rusty]

Please check if these sentences are correct and natural?
1. He's very quiet; he must be up to something! (OK).
2. Why is he being so nice to me? He must be up to something! (OK).
3. I could tell by looking at him that he must be up to something. (OK).
4. He suddenly got a mischievous grin on his face, so I suspected he must be up to something. (OK).
5. Do you know anybody who had/bore a grudge against your father? (OK).
6. These are your father's last wishes/words / this is...will.
7. According to (the provisions of) Mr. Pope's will, Miss Bridge shall/will be furnished (with) a stipend until she graduates from a college of her choice. After/Following that, she'll be provided (with) a trust, $25,000 a year for life.
(OK).