Latin Verb Stems Made Easy: Ultimate Guide for Students

Your Latin textbook – or teacher – has likely mentioned verb stems many times. This is because the three Latin verb stems provide the foundation for all other forms of a Latin verb.

Most Latin verbs have three stems.

1. The present stem
2. The perfect stem
3. The participle stem (also called the supine stem)

In this post, I will teach you how to find the verb stems for any Latin verb. I will also cover what to do with these stems and why each one matters.

This post may contain affiliate links and I may receive a commission, at no extra cost to you, if you make a purchase through a link. See my disclosures for more details.

What is a Latin verb stem?

The verb stem is the most basic part of the verb, the part to which we add endings. The verb stem stays the same across conjugated forms and thus conveys the verb’s fundamental meaning.

Take, for example, the verb audiō, which means “hear”. Its present stem is audī-. Now look at the following forms:

• audīs = you hear
• audiēns = hearing
• audiēbātur = s/he was being heard
• audiēmus = we will hear

The stem audī– appears in all these verb forms and introduces the concept of hearing. The remaining letters (s, ēns, ēbātur, and ēmus) give us further specifications. Who is hearing (or being heard)? When is the hearing occurring?

In order to understand a Latin verb, you need to be able to identify its stem AND its endings. After reading this post, you should be able to recognize Latin verb stems confidently, so you will be off to a good start!

The average Latin verb has three verb stems, and each one is used as the base for different tenses. Sometimes the three verb stems will look quite similar, as with the three stems of audiō “hear”:

1. Present stem: audī-
2. Perfect stem: audīv-
3. Participle stem: audīt-

Other times the stems may diverge a bit more, as with agō “do, act”:

1. Present stem: age-
2. Perfect stem: ēg-
3. Participle stem: āct-

Every single form of a Latin verb derives from one of these three stems.

Consequently, it is important for you to be able to find Latin verb stems. This involves looking at a verb’s principal parts.

The four principal parts of a verb are helpful forms that allow you to find each stem easily. For this reason, I highly encourage you to memorize the principal parts of each verb as you learn it.

👉 Read more about principal parts here!

Here is a visual representation of how principal parts contain a Latin verb’s three stems. Don’t worry if you are confused: we will go over everything in lots of detail below!

The Latin Present Stem

The present stem is the Latin verb stem that forms the basis for the present system.

The present system includes the present, imperfect, and future tenses. These are some of the first tenses that Latin students learn, which means that you encounter the present stem very early on in your Latin studies.

Here is a full list of the forms that are built from the present stem.

You may not recognize some or most of these forms, and that’s okay! This is just to give you an idea of the importance of the present stem.

• Present indicative active (audiō, “I hear”)
• Present indicative passive (audior, “I am heard”)
• Imperfect indicative active (audiēbam, “I was hearing”)
• Imperfect indicative passive (audiēbar, “I was being heard”)
• Future indicative active (audiam, “I will hear”)
• Future indicative passive (audiar “I will be heard”)
• Present subjunctive active (audiam, “I may hear”)
• Present subjunctive passive (audiar, “I may be heard”)
• Imperfect subjunctive active (audīrem, “I might hear”)
• Imperfect subjunctive passive (audīrer, “I might be heard”)
• Present active infinitive (audīre, “to hear”)
• Present passive infinitive (audīrī, “to be heard”)
• Present active participle (audiēns, “hearing”)
• Future passive participle / gerundive (audiendus, “about to be heard”)

This is a very long list, which means that the present stem is an important topic to understand.

It is quite easy to find a Latin verb’s present stem. You simply go to the second principal part (the present active infinitive) and remove the –re.

Practice makes perfect, as they say, so the following exercise asks you to practice identifying a verb’s present stem. Once you have finished, toggle over to the “Answers” section to check your answers!

Now you know how to find a verb’s present stem, and that’s excellent. But there is one complication that we need to address, a complication that applies to first and third conjugation verbs.

Technically, the present stem includes the characteristic stem vowel of each conjugation. So the stems of first conjugation verbs all end in –ā-. The stems of third conjugation verbs all end in –e-.

But when we combine the present stem with certain verb endings, sound changes can occur. This often results in the disappearance or transformation of the stem vowel.

I will give you one quick example. The present indicative active is constructed by adding the final personal signs directly onto the present stem.

To say “I am calling”, we take the verb vocō‘s present stem, vocā-, and then add the 1st person singular active ending: –ō. This should result in *vocāō, but this form does not exist.

Instead, the 1st person singular present indicative active is vocō. The stem vowel –ā– has disappeared in front of the –ō.

The same thing happens in the 3rd conjugation. To say “I am doing”, we would expect age- plus –ō, or *ageō. But no: the –e- disappears to give us agō.

This is why I tell my students to conceptualize the present stem as “vowel-optional”. For vocō, the stem is voc(ā)-, where the –ā– might disappear. For agō, the stem is ag(e)-, where the –e- might disappear.

The Latin Perfect Stem

The perfect stem is the Latin verb stem which forms the basis for the perfect active system. This includes the following tenses and forms:

• Perfect active indicative (audīvī, “I heard / I have heard”)
• Pluperfect active indicative (audīveram, “I had heard”)
• Future perfect active indicative (audīverō, “I will have heard”)
• Perfect active infinitive (audīvisse, “to have heard”)
• Perfect active subjunctive (audīverim, “I may have heard”)
• Pluperfect active subjunctive (audīvissem, “I might have heard”)

These tenses are called perfect (from the Latin verb perficiō, “thoroughly complete”), because they conceptualize action as completed.

The perfect stem is amazing because it never changes. No matter what ending you add, the perfect stem stays exactly the same. No need to worry about disappearing vowels!

It is also super easy to find the perfect stem. Simply remove the –ī from the verb’s third principal part (the 1st singular perfect active indicative).

Let’s look at our sample verbs.

Whenever you see a verb’s perfect stem, you know that you are dealing with a completed action of some sort. The tense must be perfect, pluperfect, or future perfect.

Time for you to practice! Can you identify the perfect stem of the following verbs?

CAUTION: Some verbs, called “impersonal”, are mostly used in the 3rd person singular. This means that their principal parts, including the third principal part, may look a little different.

EXAMPLE: decet, decēre, decuit “it is becoming, fitting”

Decuit, our third principal part, is the 3rd person singular perfect indicative active (instead of the 1st person singular perfect indicative active).

So, to find the perfect stem of impersonal verbs, remove –it from the third principal part. The perfect stem of decet is thus decu-.

The Latin Participle Stem

The last of the three Latin verb stems is the participle stem. As the name suggests, this stem gives us two types of participle: the perfect passive participle and the future active participle.

Here are the base forms built from the participle stem:

• Perfect passive participle (audītus, a, um, “having been heard”)
• Future active participle (audītūrus, a, um, “about to hear”)
• Supine (audītum, “in order to hear”, and audītū “with respect to hearing”)

This may not seem like much, but the perfect passive participle can be combined with the verb sum to produce compound forms.

So in actuality, the entire perfect passive system is also built from the participle stem:

• Perfect passive indicative (audītus sum, “I was heard / I have been heard”)
• Pluperfect passive indicative (audītus eram, “I had been heard”)
• Future perfect passive indicative (audītus erō, “I will have been heard”)
• Perfect passive subjunctive (audītus sim, “I may have been heard”)
• Pluperfect passive subjunctive (audītus essem, “I might have been heard”)
• Perfect passive infinitive (audītum esse, “to have been heard”)

Finally, the future active participle can also combine with forms of sum:

• Future active infinitive (audītūrum esse, “to be about to hear”)
• All active periphrastic forms (e.g. audītūrus sum, “I am about to hear”)

So, as you can see, the participle stem is everywhere.

To find a Latin verb’s participle stem, turn to the fourth principal part. This is usually the perfect passive participle.

In some Latin dictionaries, this form ends in –us (masculine singular). In others, it ends in –um (neuter singular). Remove the –us or –um to find the participle stem.

Now it’s your turn. Can you identify the participle stems of the following verbs?

CAUTION: Some Latin verbs cannot be made passive, so they do not have a perfect passive participle. They do, however, have a participle stem, which appears in the future active participle.

EXAMPLE: fugiō, fugere, fūgī, fugitūrus

The –ūr– in the fourth principal part tells us that this is a future active participle. To find the participle stem, then, you remove the entire –ūrus to get fugit-.

Finding the Stems of Defective Verbs

So far this post has focused on regular verbs, verbs which have all four expected principal parts. But not all verbs have four principal parts, as my post on principal parts explains.

“Defective” verbs lack certain verb tenses, and as a result, they lack the stems associated with those tenses. Here are some of the most commonly used defective verbs (according to the DCC Latin Core Vocabulary List):

• timeō, timēre, timuī – “fear”
• iaceō, iacēre, iacuī – “lie, be prostrate”
• discō, discere, didicī – “learn”
• poscō, poscere, poposcī – “demand”
• –, –, coepī, coeptus – “begin”

The first four verbs – timeō, iaceō, discō, and poscō – only have three principal parts. They are missing the perfect passive participle, and there is no future active participle to replace it.

This means that there is NO participle stem. These verbs cannot be used in the passive voice in the perfect system or have any of the other forms derived from the participle stem. You can, however, find the other two stems normally.

Coepī is an unusual case: it is a verb that only exists in the perfect system. For this reason it only has two principal parts: the 1st person singular perfect indicative active and the perfect passive participle.

We can find the perfect stem (coep-) and the participle stem (coept-) in the regular way, but there is NO present stem.

Finding the Stems of Deponent Verbs

The other major class of verbs that deserves attention here are deponent verbs. If you haven’t learned what deponents are yet, then just skip this section and jump down to my recap on finding Latin verb stems.

If you are familiar with deponents, then you likely know that they only have three principal parts. This is because they do not have active forms, so they do not have a 1st person singular perfect indicative active form to serve as the third principal part.

As a result, deponents do NOT have a perfect stem. They have only a present stem and a participle stem, and we must find them in a slightly different way.

All right, you know the drill: time for you to practice! Identify the present and participle stems of the following deponent verbs.

Recap: Finding Latin Verb Stems

Finding the stems of most Latin verbs is quite simple. Let’s review!

The second principal part gives us the present stem. Simply remove the –re and you are good to go.

EXAMPLE: The present stem of taceō, tacēre, tacuī “be silent” is tacē-.

The third principal part gives us the perfect stem. Simply remove the –ī and you have found the perfect stem.

EXAMPLE: The perfect stem of nōscō, nōscere, nōvī, nōtus “know” is nōv-.

The fourth principal part gives us the participle stem (aka the supine stem). Simply remove the –us or –um and you are done!

EXAMPLE: The participle stem of pellō, pellere, pepulī, pulsus “drive” is puls-.

See? Not so bad! Here’s the visual representation of finding the stems of audiō that I showed you at the beginning of this post. Doesn’t it make a lot more sense now?

Verb stems are important, and for this reason, principal parts are important, too. In fact, I make my Latin students memorize the principal parts of the most common Latin verbs.

(They usually hate it, but it’s good for them. Just like eating your broccoli!)

If you want to kickstart your principal parts memorization, check out my Principal Parts Study Guide. I give tips to help you memorize the principal parts of the most common 20 or so Latin verbs!

Over 1000 subscribers enjoy receiving my tips and advice, and I hope you will, too!

Principal Parts Study Guide

Subscribe to my newsletter to download this guide and work on your Latin verbs!

GET YOUR STUDY GUIDE!

You can unsubscribe at any time. Privacy Policy.

YOU MAY ALSO LOVE:

My Favorite Latin Resources

Best Apps for Learning Latin

Best Latin Dictionaries for Students

How To Find The Conjugation of Any Latin Verb

How To Read Latin (More) Easily: Practical Tips

Latin Subjunctive Demystified