Yang pinter B.Inggris tolong jawabkan 1 - 5 aja dong, mau dikumpul besok nih. mahon bantuannya

1. to sit down
2. if i smoked
3. i had used to smoke
4. i had stopped smoking the previous year
5. where i had worked before
6. i spent five years with an architect
7. if i could take shorthand
8. i could, of course
9. he would give me the job on one month's probation
10. ?
11. ?
12. ?