a. A conditional sentence is usually composed of two parts – The condition and the consequence.
In the condition we usually use the past simple of the verb (was, had). In the consequence we use would + infinitive without to (would speak, would go): Examples: If there was a problem with his room, he would speak to the manager.
If I had the money and also the time, I would go to New York.
We always separate the consequence and the condition with a comma, when we begin the sentence with the condition. When we begin the sentence with the consequence, we usually don’t use a comma. Example: I would go to New York if I had the money and also the time.
b. The negative form of 'would' is 'wouldn't': Example: If there was a problem with his room, he wouldn't contact his travel agent
c. When you make a question, you change the word order by moving 'would': Examples: What would you do if there was a problem with your room? If you had the money and also the time, where would you go? Would you contact your travel agent? Would you visit the Statue of Liberty?
d. In short answers to yes/no questions, you use would or wouldn't? Examples: Would you contact your travel agent? No, I wouldn't. Would you visit the Statue of Liberty? Yes, I would.
e. In spoken English, we usually use a contracted form of would: I would = I'd, he would = he'd etc.
f. It is possible, in the condition, to say both 'If I were you ...' and 'If I was you ...' 'If I were you ...' is the traditional and more formal form, but 'If I was you ...' is very common nowadays.
Listen to the Flatmates episode 192