Learners seem to find it easier to mark past tense on verbs that refer to something whose end point can easily be determined. These are referred to as ‘accomplishments’ and ‘achievement’ [‘I ran three miles. My brother took an aspirin and went to bed’]. For ‘activities’ that may continue for some period [‘I swam all afternoon’] or ‘states’ that may be perceived as constants [‘He seemed happy to sit by the lake’], learners use simple past markers less frequently. First language can have an influence here too. Laura Collins [2002] investigated the different English verb forms used by French speakers.