1. Sales have been down these days.
2. sales have been up these days.
(Are both right?)
3. If they hadn''t helped me, I would be poor.
4. As they helped me, I am not poor.
(Does #3 mean #4?)
5. If it hadn't rained hard yesterday, the road wouldn't be muddy.
6. As it rained hard yesterday, the road is muddy.
(Does #5 mean #6?)
7. If he weren't here, I couldn't have seen him in the hallway.
8. As he is here, I could see him in the hallway.
(Are both the same in meaning?)