Present Tense

A present tense is a tense expressing an action that is currently going on or habitually performed or a state that currently or generally exists. Present tense shouldn't be confused with the present perfect progressive or other progressive forms.

Using present tense to describe current actions

The present tense is a very simple grammatical form—so simple, in fact, that it is often only used for certain simple purposes. Usually, the present tense consists of just the base form of a verb, with no modification. Learn more about verbs and the different tenses. 

The present tense is used either to express an action that habitually occurs over time, or to describe the qualities or properties of a given noun. 

The present tense can also be used for immediacy within narrative writing, although this is a relatively uncommon use of the tense.  

Academic writing and the present tense

Here is an example of the present tense being used correctly within a sentence. 

"The sky is blue, and roses are red, and—well, the old children's rhyme goes something like that, as everyone knows."

In this sentence, is, are, goes, and knows are correct uses of verbs in the present tense. 

Now, here is an example of the present tense being used in an incorrect way. 

"I walk to the park, but then I turned around when I heard a stranger address me from behind in an oddly familiar way." 

In this sentence, "walk" is incorrect, because the rest of the sentence is in the past tense. 

In case you are still a little confused about the present tense, here are a couple basic rules you can follow in order to make sure you are using it in a proper way. 

1. The present tense really only has three uses. The first is to say something that happens on a habitual basis, such as walking or raining. The second is to describe the properties of an object, such as color or size. And the third is to convey narrative immediacy. Other than these uses, the present tense is actually quite obscure in English. 
2. The present tense almost tends to convey a sense of a kind of eternal now. Its use generally lacks context, and it gives the impression that what is being said is permanently or "essentially" true in some way. If you want to introduce any further context to your statements, you would need to shift away from the simple present tense.  

Simplicity of the term

Given the simplicity of the present tense, it is perhaps strange that it is not used more frequently in ordinary language. Then again, this makes sense if one bears in mind that the present tense does not so much describe an action as essential properties or states of being; this is not generally what people need language for in everyday life.

On the other hand, the present tense may be quite useful in intellectual or philosophical discourse, where the main aim is to define and/or analyze objects in a careful way.  

An exception to this is when the present tense is used within the context of a narrative. This is almost always done to provide a sense of enhanced immediacy. For example, if you say that you "walked with the old man", then this makes the reader feel relatively safe and/or detached.

But if you say, within the context of a specific situation, that you "walk with the old man", then this is immediate almost to the point of eeriness. There is a sense of danger, even: anything could happen. The narrative voice is usually in the past tense, but the present tense could in fact be used for this kind of dramatic effect.