Almost every English sentence has a ‘time’ and a ‘place’, which are sometimes explicitly stated and sometimes only implied. One question in the textbook was (something like) ‘I ___ (work) at 7 o’clock this evening. I work till 8 on Thursdays.’ The first question to be mentally answered is ‘What day is it today-in-this-sentence?’. Some students said ‘Wednesday’ (because it really was), but my interpretation is that ‘today-in-this-sentence’ is Thursday, because if it was any other day, then the information about Thursday would violate Grice’s maxim of relevance. If it is Thursday, then the answer is ‘I will be working at 7 o’clock’. If it is any other day, then it’s ‘I won’t be working’ (but textbooks and tests usually supply ‘not’ if a negative statement is needed).
Another question was ‘You can’t / may have seen Gary here yesterday. He took the day off.’ The question is ‘Where is “here”?. If ‘here’ is ‘the office’, then you can’t have seen him here yesterday. If ‘here’ is ‘his favourite pub’, then you may have. (Or you might have.)