How And When to Use Perfect Tense

Simple and Perfect Tense

What is the difference between these three sentences?

• I finished my homework.
• I finish my homework.
• I will finish my homework.

While they are all describing the same action, these sentences describe different times in which that event is happening. The time in which an event is happening, as expressed by the form of the verb used, is called a verb tense.

At first, verb tenses might seem pretty straightforward. If the event is happening right now, you use the present participle of the verb, which is just its most basic form (walk, run, catch, etc). If it is in the past, you use the past participle, in which the verb is changed (walked, ran, caught). And future tense is usually expressed by adding 'will' before the present participle.

So, that's verb tenses. Pretty easy, right? But of course, it's not that easy, as these three forms are the simple verb tenses, known as simple past, simple present, and simple future.

There is another set of verb tenses known as the perfect tense: past perfect, present perfect, and future perfect. While at first these more confusing tenses may seem like they were just the invention of sadistic English teachers so they could get their red-pen jollies, the perfect tenses are important for expressing more complex ideas about when certain events happened.

Past Perfect

Past perfect might be the easiest to wrap your head around. This describes an event that not only happened in the past, but was completed before something else happened. So, let's say you're telling your parents what happened to the family car you borrowed:

I filled the car up with gas.

But they're wondering why the gas tank is on empty now, so you need to add some more information:

I had filled the car up with gas before I used it to drive to Cancun.

The action 'filled' was completed before the other event (driving to Cancun), so it has changed from the simple past to the past perfect tense, as shown by the addition of the helping verb 'had.' Past perfect is typically expressed as a combination of 'had' and the past participle of the verb.

Present Perfect

Present perfect is pretty similar, but brings the events into the here and now. It describes an event that started in the past and is still going on right now. So, in simple present I might say:

I teach English at Hamilton High School.

But what if I want to be more expansive and talk about how long I've been doing this same action? Then it would look like this:

I have taught English at Hamilton High School for ten years.

This is present perfect tense. You'll notice I use the past participle, but instead of 'had,' I use 'have' to indicate it is still going on. Present perfect is typically expressed with 'have' or 'has' followed by the past participle.

Future Perfect

Future perfect tense is probably the one that gives people the most trouble because its explanation can get a little mind-bending. The definition for future tense is that it describes an action that will have been completed before a certain time in the future.

So, what does that mean? Let's look at some examples, which are easier than wrapping your head around that explanation. So, let's say you want to start working out, you might express it like this:

I will exercise 60 minutes everyday.

But if you're like me, you maybe need a little more motivation and set a more specific goal. This is where the future perfect comes in handy:

By Friday, I will have exercised a total of seven hours.

This version sets a certain point in the future by which time the action will be done. That's future perfect. Future perfect is expressed by basically combining simple future and present perfect. You add 'will' before the present perfect combo of 'have' and the past participle.