The tenses simply show the time of an action or state of being as shown by a verb. Tenses are usually manifested by the use of specific forms of verbs, particularly in their conjugation patterns. Time can be split into three periods: the present, the past and the future.
Further, in English language we use two tenses to talk about the present and six tenses to talk about the past. There are, however, several ways to talk about the future, some of which use the present tenses. The tenses are as follows:
Simple tenses. The simple tenses are used to show traits or characteristics of people and events, or what happens regularly. The simple present tense of a verb expresses habits and general truths. The simple past talks about a completed action in a time before ‘now’. The simple future refers to a time later than the present, and expresses certainty.
Continuous tenses. The continuous tenses are used when talking about a particular point in time. The present continuous expresses something that is unfinished or incomplete. The past continuous denotes an action going on at some time in the past. The future continuous tense is used to talk about actions which will be in progress at a certain time in future.
Perfect tenses. The perfect tenses are used when an action or situation in the present is linked to a moment in the past. The present perfect is used to indicate completed activities in the immediate past (with just). The past perfect describes an action completed before a certain moment in the past. The future perfect is used to talk about actions that will be completed by some point of time in future.
The present perfect continuous is used for an action which began at some time in the past and is still continuing. The past perfect continuous is used for an action that began before a certain point in the past and continued up to that time. The future perfect continuous tense is used for actions which will be in progress over a period of time even after a given point of time.