14 / PART ONE: THE BASICS Ken has cooked the dinner. Chris has written a letter to his mother. The first three participles in the examples above are the same as the ordinary past tense but ‘has’ or ‘had’ have been added. These are regular verbs and the past participle ends in ‘-ed’. In the last example ‘written’ is different and can only be used with the verb ‘to have’. A number of verbs are irregular, including the following: infinitive past tense past participle to be was/were been to break broke broken to build built built to do did done to drink drank drunk to drive drove driven to fall fell fallen to feel felt felt to fling flung flung to fly flew flown to leap leapt leapt to run ran run to sleep slept slept to swim swam swum to tear tore torn to win won won to write wrote written When the verb ‘to have’ is added to the past participle, the finite verb is either the present perfect or the past perfect tense. This depends on which tense of the verb ‘to have’ has been used.