1. wrote - haven't received
-> S have/has not VPII since ...
2. is
-> Câu điều kiện loại I, vế đầu chia HTĐ
3. will call
-> TLĐ as soon as HTĐ
4. to smoke
-> used to Vnt
5. be corrected
-> S must be VPII by O.
6. haven't finished
-> S have/has not VPII