The simple answer is: Any verb that doesn't follow standard rules of conjugation. Unfortunately, there are so many "irregular" verbs in the English language that the title doesn't really make sense. These grammar anomalies have been lurking in plain sight for years, and they might just come naturally to you, but we're still going to take a closer look.
Irregular Verbs and the Past Tense
Typically, it's correct (and easy enough) to say the past tense of a verb ends in an "-ed." For example, “I drop the kids off in the morning” in the present tense becomes, “I dropped the kids off this morning.” Or, “I scrub the dishes,” in the present changes to “I scrubbed the dishes” in the past tense. Those two letters added to the end of a word are a pretty good indicator of past tense.
Then you come across a verb like "speak." In the present tense, you’d say, “I speak.” In the past tense, you would not say, “I speaked.” Instead, you’d say, “I spoke.”
Boom. You’ve just found an irregular verb. As you might have guessed, irregular verbs break the standard rule of ending in "-ed" in the past tense.
To further confuse the issue, irregular verbs have no discernible pattern themselves. They're just ... irregular. These irregular verbs are some of the most commonly used in English — "go," "say," "see," "think," "make," "take," "come," and "know." These workhorse verbs take on different spellings in the past tense.
In general, irregular verbs are easy enough to spot in the past tense — if it doesn’t end in "-ed," it’s irregular.
Spotting More Irregular Verbs
Test yourself: Which of these examples of irregular verbs are correct?
- She drunk the glass of water.
- The phone rung and rung.
- The pants shrank in the dryer.
Answer: Only number three is correct. In one, the correct past tense is "drank," and in number two, the phone "rang."
It’s still quite easy to get confused by irregular verbs, especially when you look at the difference between simple past tense and past participles (in which case, "shrunk" would be the past participle in example three above).
For example, “Stacy drived to the public pool where she swum for hours.” Hopefully this sounds wrong to your ears, because it’s just an irregular mess.
There are two irregular verbs in this example, but neither is correct. The first is obvious – "drived" attempts to follow the regular verb "-ed" ending. It sounds awkward, because it’s not a real word at all. The correct (irregular) past tense is "drove."
The second one is a little trickier. "Swum" is in fact the past participle of the verb "to swim," but it's not the simple past, which is "swam."
The correct version of Stacy's day at the pool is, “Stacy drove to the public pool where she swam for hours.”
As confusing as irregular verbs may seem, they start to come naturally with practice. What irregular verbs do you still stumble over?