1. (prefix) can; may; able to; -able
2. to approve; to permit
3. to suit
4. (particle used for emphasis) certainly; very
5. but; however

1. letter
2. mail
3. to trust
4. to believe
5. to profess faith in
6. truthful
7. confidence
8. trust
9. at will
10. at random

classifier: 封