A verb expresses action, event, state of being, state of happening etc. For example:

ਜਾ go
ਕਰ kar do
ਸੁਣ suṇ listen
ਹੱਸ hass laugh

Above are all verbs.

In sentences, these single word verbs are occasionally used and frequently lengthier phrases are used as compound verbs. For example:

ਜਾਂਦਾ ਹੈ, ਕਰ ਰਿਹਾ ਸੀ, ਸੁਣਿਆਂ ਕਰਾਂਗੇ, ਹੱਸਦੇ ਰਹਿੰਦੇ ਹਨ

In a Punjabi sentence, verbs must agree with the subject or object of the sentence in terms of gender, number, and person. A Punjabi verb root is always in second person singular form in imperative mood.

Punjabi verbs change forms for gender, number, person, phase, and tense. These verbs have assigned transitivity and causality.

  Transitive verbs are those that require an object in a sentence unlike intransitive verbs.
For example:
ਹੱਸ is intransitive as in ਮੁੰਡਾ ਹੱਸ ਰਿਹਾ ਸੀ |
ਲਿਖ is transitive as in ਉਸਨੇ ਚਿੱਠੀ ਲਿਖੀ |

Some verbs may be used as both transitive and intransitive.
For example:
ਖੇਡ is transitive in ਮੁੰਡਾ ਹਾਕੀ ਖੇਡ ਰਿਹਾ ਹੈ | 
but intransitive in ਮੁੰਡਾ ਖੇਡ ਰਿਹਾ ਹੈ |

Some verb roots extend to form causatives. There are two types of causatives – simple and double. In general, the simple causative is formed by adding and double by adding ਵਾ.
For example: 
  Forms of verb root ਰੱਖ are ਰਖਾ (simple causal) and ਰਖਵਾ (double causal).
All the causatives are transitive irrespective of the transitivity of their root.

There are two genders – masculine and feminine for which Punjabi verbs change forms.

Like other word classes, Punjabi verbs change forms for two numbers – singular and plural.

Punjabi verbs take forms for three persons – first, second, and third accoding to the subject of the sentence.

Punjabi verbs can be in perfect or non-perfect forms. Prefect refers to the action completed or perfected at the time of saying and non-prefect refers to the remaining states of the action like ongoing or not started.

Punjabi verbs take forms for future tense only and for present and past tense, appropriate auxiliary verb form (for present or past tense) is used. For example: 

ਜਾਂਦਾ ਹੈ jāndā hai is going
ਜਾਂਦਾ ਸੀ jāndā sī was going
ਜਾਵੇਗਾ jāvēgā will go

Please note that for future tense, no auxiliary verb is used.

Verb-Part: The words of this word class do not change forms. It differs from other similar word classes in the sense that the words of this word class can only be used as a part of a verb phrase in a sentence.
For example, ਰਿਹਾ rihā is a verb-part in the following sentence:
ਕੈਦੀ ਜੇਲ੍ਹ ਵਿੱਚੋਂ ਰਿਹਾ ਹੋ ਗਿਆ ਹੈ।
kaidī jēlh viccōṃ rihā hō giā hai.
The prisoner have been freed from the prison.

Various forms of a Punjabi verb root based on above mentioned grammatical categories can be classified into 14 inflectional classes, which serve the purpose of ‘mood’. These inflectional classes are U, O, E, NA, DA, IA, IDA, EGA, DIAN, IAN, NON, N, KE, and DON. Out of these DIAN, IAN, NON, N, and KE are termed as non-finite and show no inflection, rest all the classes are termed finite and show inflection for gender, number, and person.

For example, inflectional class wise grouping of the forms (or paradigm) of verb ਜਾ ‘go’ are provided here, U – ਜਾਊਂ jāūṃ and ਜਾਊ jāū, O – ਜਾ , ਜਾਈਂ jāīṃ, and ਜਾਇਓ jāiō, E – ਜਾਣ jāṇ, ਜਾਵਾਂ jāvāṃ, ਜਾਈਏ jāīē, ਜਾਓ jāō, ਜਾਏਂ jāēṃ, and ਜਾਏ jāē, NA – ਜਾਣਾ jāṇā, ਜਾਣੇ jāṇē, ਜਾਣੀ jāṇī, and ਜਾਣੀਆਂ jāṇīāṃ, DA – ਜਾਂਦਾ jāndā, ਜਾਂਦੇ jāndē, ਜਾਂਦੀ jāndī, and ਜਾਂਦੀਆਂ jāndīāṃ, IA – ਗਿਆ giā, ਗਏ gaē, ਗਈ gaī, and ਗਈਆਂ gaīāṃ, IDA – ਜਾਈਦਾ jāīdā, EGA – ਜਾਵਾਂਗਾ jāvāṅgā, ਜਾਵਾਂਗੇ jāvāṅgē, ਜਾਵਾਂਗੀ jāvāṅgī, ਜਾਵਾਂਗੀਆਂ jāvāṅgīāṃ, ਜਾਵੇਗਾ/ਜਾਏਗਾ jāvēgā/jāēgā, ਜਾਵੋਗੇ/ਜਾਓਗੇ jāvōgē/jāōgē, ਜਾਵੇਗੀ/ਜਾਏਗੀ jāvēgī/jāēgī, ਜਾਵੋਗੀਆਂ/ਜਾਓਗੀਆਂ jāvōgīāṃ/jāōgīāṃ, ਜਾਵੇਂਗਾ/ਜਾਏਂਗਾ jāvēṅgā/jāēṅgā, ਜਾਵੇਂਗੀ/ਜਾਏਂਗੀ jāvēṅgī/jāēṅgī, ਜਾਣਗੇ jāṇgē, and ਜਾਣਗੀਆਂ jāṇgīāṃ, DIAN – ਜਾਂਦਿਆਂ jāndiāṃ, IAN – ਗਿਆਂ giāṃ, NON – ਜਾਣੋਂ jāṇōṃ, N – ਜਾਣ jāṇ, KE – ਜਾਕੇ jākē, and DON – ਜਾਂਦੋਂ jāndōṃ, ਜਾਂਦਿਓ jāndiō, and ਜਾਂਦੀਓ jāndīō. Other verb roots may have more or less forms than these described here for ਜਾ ‘go’. U, O, and EGA forms are for future tense. IA, IAN, and KE forms are classified as perfect forms and all others are non-perfect.

Punjabi main verbs, on an average have 48 distinct forms, unlike English verbs, which usually have only five different forms.

Auxiliary Verb

In Punjabi, there are two auxiliary verbs – ਹੈ hai for present tense and ਸੀ for past tense. All the forms of these two auxiliary verbs can equally be used for both the genders. For future tense in sentences, EGA form of main verb is used and in those sentences auxiliary verb is thus not used. There are two Punjabi auxiliary verbs, ਹੈਗਾ haigā and ਸੀਗਾ sīgā, which change forms with gender. ਹੈਗਾ haigā and ਹੈਗੀ haigī are present tense forms for masculine and feminine gender respectively. Corresponding forms for past tense are ਸੀਗਾ sīgā and ਸੀਗੀ sīgī.

Grammatical categories:
Auxiliary verbs change forms with number and person.

There are two numbers – singular and plural.

Person: There are three persons – first, second, and third, for which Punjabi auxiliary verbs change forms.

Various forms of present tense auxiliary verb ਹੈ hai are – ਹਾਂ hāṃ (first person form for singular and plural numbers), ਹੈਂ haiṃ (singular second person), ਹੋ (plural second person), ਹੈ hai (singular third person), and ਹਨ han (plural third person). There are two infrequent forms of ਹੈ hai – ਹਓ haō (plural second person) and ਹੈਣ haiṇ (plural third person).

Various forms of past tense auxiliary verb ਸੀ are – ਸੀ (applicable for all three persons and both the numbers), ਸਾਂ sāṃ (singular and plural numbers for first person), ਸਨ san (plural third person), ਸੋ (plural second person), ਸੈਂ saiṃ (singular second person). Some less frequently used forms of ਸੀ are – ਸਓ saō, ਸਾਓ sāō, and ਸਉ sau. These three forms are used with second person plural subjects in sentences.
ਹੈਸੀ haisī and ਹੈਸਣ haisaṇ are two past tense auxiliary verbs used respectively with singular and plural forms of third persons. These forms, like the forms of ਹੈ hai and ਸੀ , can be used with both the genders.

Some colloquial present tense auxiliaries are used in place of the corresponding forms of ਹੈ hai. These colloquial forms are more prominent in informal speech than writing. ਆਂ āṃ (singular first person and plural first person), ਏਂ ēṃ (singular second person), ਓ ō (plural second person), ਏ ē (singular third person), and ਨੇ (plural third person) constitute these colloquial forms applicable for both the genders.

Different forms of gender specific auxiliary verbs are ਹੈਗਾ haigā (masculine singular present tense), ਹੈਗੇ haigē (masculine plural present tense); ਹੈਗੀ haigī (feminine singular present tense), ਹੈਗੀਆਂ haigīāṃ (feminine plural present tense); ਸੀਗਾ sīgā (masculine singular past tense), ਸੀਗੇ sīgē (masculine plural past tense); ਸੀਗੀ sīgī (feminine singular past tense), ਸੀਗੀਆਂ sīgīāṃ (feminine plural past tense). All these forms are applicable for all the three persons.