5. New Grammar: Third Conditional

What do you think – what would have prevented the accident? In order to speculate about this past event (and, possibly, in order to express regret), you need to use a grammar point called the third conditional. First, read about it in this grammar overview and make sure you are able to distinguish between the following conditional types: the zero conditional, first conditional, second conditional and third conditional. Then practise this grammar point in a general English context first by completing this gap-fill exercise and this reading exercise.