Theoretical Grammar

Present Past

Future I Future II

Generally speaking, the major tense-distinction in English is undoubtedly that which is traditionally described as an opposition of past::present. But this is best regarded as a contrast of past:: non-past. Quite a lot of scholars do not recognize the existence of future tenses, because what is described as the 'future' tense in English is realized by means of auxiliary verbs will and shall. Although it is undeniable that will and shall occur in many sentences that refer to the future, they also occur in sentences that do not. And they do not necessarily occur in sentences with a future time reference. That is why future tenses are often treated as partly modal.
5. The Category of Aspect
The category of aspect is a linguistic representation of the objective category of Manner of Action. It is realized through the opposition Continuous::Non-Continuous (Progressive::Non-Progressive). The realization of the category of aspect is closely connected with the lexical meaning of verbs.
There are some verbs in English that do not normally occur with progressive aspect, even in those contexts in which the majority of verbs necessarily take the progressive form. Among the so-called ‘non-progressive’ verbs are think, understand, know, hate, love, see, taste, feel, possess, own, etc. The most striking characteristic that they have in common is the fact that they are ‘stative’ - they refer to a state of affairs, rather than to an action, event or process. It should be observed, however, that all the ‘non-­progressive' verbs take the progressive aspect under particular circumstances. As the result of internal transposition verbs of non-progressive nature can be found in the Continuous form: Now I'm knowing you. Generally speaking the Continuous form has at least two semantic features - duration (the action is always in progress) and definiteness (the action is always limited to a definite point or period of time). In other words, the purpose of the Continuous form is to serve as a frame which makes the process of the action more concrete and isolated.