a 2. could provide 3. lacks 4. won't be 5. had built 6. might not have lost 7. would still be working 8. hadn't messed up 9. were 10. would have noticed 11.aren't 12. will call.
b 2 If I had saved some money, I wouldn't be broke.
3. You can borrow my laptop on condition that you look after it.
4. I'm going to the party whether I'm invited or not.
5. Supposing you hadn't found your passport, what would you have done?
6. Your exam will be fine providing (that) you do enough revision.
7. I'm favour of contact sports as/so long as nobody gets seriously injured.
8. I would never wear fur, even if the weather (it) was very cold.
9. You can go out tonight provided (that) you're back by midnight.