1. B -> S + might + have + V3/ed
2. A -> S + could + have + V3/ed
3. B -> S + must + have + V3/ed: ắt hẳn đã
4. A -> S + shouldn't + have + V3/ed: lẽ ra không nên
5. C -> S + may + have + V3/ed
6. B -> S + might + have + V3/ed
7. A -> S + should + have + V3/ed: lẽ ra nên
8. A -> S + could + have + V3/ed
9. C -> S + shouldn't + have + V3/ed: lẽ ra không nên
10. C -> S + couldn't + have + V3/ed
11. D -> S + must + have + V3/ed: ắt hẳn đã
12. D -> S + should + have + V3/ed: lẽ ra nên
13. C -> S + could + have + V3/ed
14. B -> S + should + have + V3/ed: lẽ ra nên
15. D -> S + might + have + V3/ed
16. A -> S + needn't + have + V3/ed: đáng lẽ không cần
