21. If it didn't rain heavily, Nick could go now.
Unless it rained heavily, Nick could go now.
22. If David weren't so clumsy, he wouldn't have so many accidents.
Unless David were so clumsy, he wouldn't have so many accidents.
23. If Susan had a watch, she wouldn't be late for work.
Unless Susan didn't have a watch, she wouldn't be late for work.
24. If he didn't smoke forty cigarettes a day, he won't cough a lot.
Unless he smoked forty cigarettes a day, he won't cough a lot.
25. If they had a garden, they would grow vegetables.
Unless they didn't have a garden, they would grow vegetables.
26. If I had a boat, I would sail around the world.
Unless I didn't have a boat, I would sail around the world
