Conditional mood

1. First

1.1. If + Simple Present; Simple Future

1.2. If it rains, I will stay at home.

2. Second

2.1. If + Simple Past; Present conditional or Present continuous conditional

2.2. If it rained, I would stay at home.

3. Third

3.1. If + Past Perfect; Present Conditional

3.2. If it had rained, I would have stayed at home.

4. Mixed

4.1. If + Past Perfect; Present Conditional

4.2. If you had not cut your finger, it would not bleed now.

5. Zero

5.1. If + Simple Present; Simple Present

5.2. If you cut your finger, it bleeds.

6. Linking Words

6.1. UNLESS

6.1.1. I will go running tomorrow, unless it rains.

6.2. IF ONLY

6.2.1. If only I had more freetime, I would go running.

6.3. BUT FOR

6.3.1. But for your advice, I would not have known what to do.

6.4. PROVIDED THAT

6.4.1. You can go running provided that the weather is nice.