We use the conditional mood to talk about imagined or hypothetical situations. It is formed with the auxiliary "would" followed by the infinitive of the main verb. Some examples of its use include saying "It would be nice to buy a new car but we can't afford it" and "I would phone Peter but I don't have his number." The conditional mood can also be used to talk about what someone would or wouldn't do, such as "She wouldn't pass the driving test if she drove more carefully."