 Difference between should, could, and would from espressoenglish.net Use should and shouldn't for advice and suggestions. For example, I have a really bad headache. You should go to the doctor. I need to lose some weight. Well, you shouldn't eat so much fast food. I had a fight with my best friend. What should I do? I think you should call her and say you're sorry. Could and couldn't are the past forms of can and can't. Use them for ability in the past. For example, when I was younger I could run a mile in seven minutes. Yesterday I couldn't find my wallet anywhere. This morning I found it on top of the fridge. Last year John couldn't speak English very well, but he's improved a lot recently. You can also use could for possibilities in the future. For example, how are we going to get from the airport to the hotel? Well, we could take the bus. If it's really late at night, we could take a taxi instead. Finally, you can use could to make polite requests. Could you open the window? Could you turn down the TV? Could you make ten copies of this report, please? Could you lend me your pen? Use would and wouldn't for unreal, unlikely or imaginary situations. For example, if I were president of the country I would make a lot of changes. If you had called me and told me you weren't coming I wouldn't have wasted an hour waiting for you. Would is often shortened to apostrophe D. If I were president I'd make a lot of changes. You can use the phrase would you like to make polite offers. Would you like anything to drink? We're going to the park this weekend. Would you like to join us? Finally, never use to after should, could or would. You shouldn't smoke. We could order pizza tonight. I would buy a car if I had the money. Visit www.espressoenglish.net for more English tips. If you like this video, please share.