The present tense is a grammatical tense whose principal function is to locate a situation or event in present time.〔Comrie, Bernard, ''Tense'', Cambridge University Press, 1985.〕 The term "present tense" is usually used in descriptions of specific languages to refer to a particular grammatical form or set of forms; these may have a variety of uses, not all of which will necessarily refer to present time. For example, in the English sentence ''My train leaves tomorrow morning'', the verb form ''leaves'' is said to be in the present tense, even though in this particular context it refers to an event in future time. Similarly, in the historical present, the present tense is used to narrate events that occurred in the past.
There are two common types of present tense form in most Indo-European languages: the present indicative (the combination of present tense and indicative mood) and the present subjunctive (the combination of present tense and subjunctive mood).
Present tense may be denoted by the glossing abbreviation or .
The present indicative of most verbs in modern English has the same form as the infinitive, except for the third-person singular form, which takes the ending ''-()s''. The verb ''be'' has the forms ''am'', ''is'', ''are''. For details see English verbs. For the present subjunctive, see English subjunctive.
A number of multi-word constructions exist to express combinations of present tense with aspect. The basic form of the present tense is called the simple present; there are also constructions known as the present progressive (or present continuous) (e.g. ''am writing''), the present perfect (e.g. ''have written''), and the present perfect progressive (e.g. ''have been writing'').
Use of the present tense does not always imply present time. In particular, the present tense is often used to refer to future events (''I am seeing James tomorrow''; ''My train leaves at 3 o'clock this afternoon''). This is particularly the case in condition clauses and many other adverbial subordinate clauses: ''If you see him,...''; ''As soon as they arrive...'' There is also the historical present, in which the present tense is used to narrate past events.
For details of the uses of present tense constructions in English, see Uses of English verb forms.
Positive: S + V1 (s / es)
Negative: S + DO / DOES + NOT + V1
Question: DO / DOES + S + V1
It is used to express an action in present time, habitual or usual actions, a daily event or a universal fact. It is used to express an action in present time which is usually performed on a regular basis. For example a student says, "I go to school." It is a daily activity of a student to go to school, so such actions are expressed by the present simple tense.
• Subject + Main verb + Object
• Subject + 1st form of verb (or base verb) + Object
Note: If the subject in a sentence is ''he'', ''she'', ''it'', or a singular noun, then “s” or “es” is added to the base form of the verb.
I write a letter.
He gets up early in the morning.
The Sun rises in the east.
• Subject + auxiliary verb +NOT + Main verb +object
• Subject + Do not/Does not + 1st form of verb (or base form) + object
I do not write a letter.
He does not get up early in the morning.
The Sun does not rise in the north.
Note: In a negative sentence the auxiliary verb "do" or "does", along with "not", is used. If the subject in a sentence is ''he'', ''she'', ''it'', or a singular noun, then “Does not” is used after the subject in the sentence. Otherwise, “Do not” is used after subject in sentence. “s” or “es” is not added to the main verb in a negative sentence.
• Auxiliary verb + Subject + Main verb + Object
• Do/Does + Subject + 1st for of verb (or base verb) + Object
Does he get up early in the morning?
Does the Sun rise in the east?
I sing a song.
He drinks water.
They read lessons.
John reaches home in time.
Water maintains its surface level.
He does not drink water.
They do not read lessons.
Birds do not chirp.
John does not reach home in time.
Water does not maintain its surface level.
Does he drink water?
Do they read lessons?
Do birds chirp?
Does John reach home in time?
Does water maintain its surface level?
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