By tense we understand the correspondence between the form of the verb and our concept of time (present, past or future), aspect concerns the manner in which a verbal action is experienced or regarded (ie as complete or in progress). Since tense relates the meaning of the verb to a time scale we should first pay attention to the different kinds a verb may have. Thus, in a broad sense, verbs may refer either to an event (ie a happening thought of as a single occurrence, with a definite beginning and end) or to a state (ie a state of affairs which continues over a period and need not have a well-defined beginning and end). This does not mean that there is real distinction between these verbs, it is sooner a conceptual one, as the same verb can change from one category to another and the distinction is not always clear. The difference between state and event presupposes the following kinds of verb meaning:  state – He is a scientist. single event – He leads the department of physics. set of related events (habit) - He meets a lot of people at scientific gatherings. To these, another type of verbal meaning can be added, ie the temporary meaning expressed by the progressive aspect. e. g. She was preparing supper.  The meaning of the progressive aspect is „limited duration”. For comparison, let’s analyse the two present forms, that of simple present and present progressive, in parallel examples:  It rains a lot in autumn. (habit) - I can’t leave the house, it’s raining hard He usually sleeps well. (habit) - I am sorry, you can’t have him on the phone, he is sleeping. They live in the country. (permanently) - They are living in town now. (temporary) So, we can conclude that, for single events which involve a limited time-span, the efect of progressive is to point out the durational aspect of the event:  He serves in the army. (at this moment). He is serving in the army. (the service is a continuing activity) Used with state verbs, the effect of the progressive is to put emphasis on the limited duration of the state of affairs: They live in the country. (permanently). They are living in town now. (temporarily) Present progressive is used to express temporary habit, thus combining the temporary meaning of the progressive with the repetitive meaning of the habitual present. Accompanied by always or similar adverbs of indefinite time, the present progressive conveys not temporariness but continuousness. She is always (continually) interrupting people. This use of the progressive aspect carries with it some feeling of disapproval. There is anorher case when temporary and habitual meanings are combined to show a repetition of temporary happenings. She is cooking something whenever I come to see her. Thus, the joint and parallel investigation of the two present forms – simple present and present progressive helps the learners to see and feel the difference of the verbal meanings.  The progressive aspect refers to activity in progress, therefore it shows not only that the activity is temporary (ie of limited duration), but that it need not be complete. This meaning is best seen in the past tense from the examples given below. He wrote a book two years ago. (he finished it) He was writing a book two years ago. (it is not clear whether he finished it) In a similar way, the verbs referring to a change of state, the progressive aspect indicates movement towards the change, rather than completion of the change itself. The woman was falling. (but at the last moment somebody came to her rescue). When it is linked to a non-progressive event verb, or to a point of time, the progressive usually indicates that at that point the activity is still in progress, that it has started but has not yet finished. At two o’clock when I came in they were (already) having dinner. It means that dinner has started before 2 o’clock or the moment I came in, and it still continued after that.We should distinguish between verbs taking and not taking progressive. Typically the verbs denoting activities (read, write, work) or processes (grow, improve, change) take progressive and those denoting momentary events (nod, jump, knock) used with the progressive suggest repetition. He nodded. (one movement of the head). He was nodding. (repeated movements of the head) State verbs usually do not take the progressive, but there are special circumstances in which they are used, thanks to the fact of being changed into activity verbs and being replaced by synonymic activity verbs as it follows, the verbs look at and listen to are used in place of see and hear. I am looking at you. She was listening to the news when I rang up.