The Verb "Undergo" in English

Conjugation of "To Undergo"

The verb "undergo" is an irregular verb. (This means that "undergo" does not form its simple past tense or its past participle by adding "-ed" or "-d" to the base form.)

The Five Forms of "To Undergo"

Form	undergo	Alternative Name
Base Form	undergo	Infinitive Form
The -S Form	undergoes	Third Person Singular Form
Past Form	underwent	Simple Past Tense
The -ING Form	undergoing	Present Participle Form
The Past Participle Form	undergone	[no alternative name]

"To Undergo" in All the Tenses

The tables below show how "undergo" conjugates in the past, present, and future tenses.

Past Tenses

Person	Simple Past	Past Progressive Tense	Past Perfect Tense	Past Perfect Progressive Tense
I you he/she/it we you they	underwent underwent underwent underwent underwent underwent The simple past tense is for a completed activity that happened in the past.	was undergoing were undergoing was undergoing were undergoing were undergoing were undergoing The past progressive tense is for an ongoing activity in the past. Often, it is used to set the scene for another action.	had undergone had undergone had undergone had undergone had undergone had undergone The past perfect tense is for emphasizing that an action was completed before another took place.	had been undergoing had been undergoing had been undergoing had been undergoing had been undergoing had been undergoing The past perfect progressive tense is for showing that an ongoing action in the past has ended.

Present Tenses

Person	Simple Present	Present Progressive Tense	Present Perfect Tense	Present Perfect Progressive Tense
I you he/she/it we you they	undergo undergo undergoes undergo undergo undergo The simple present tense is mostly for a fact or a habit.	am undergoing are undergoing is undergoing are undergoing are undergoing are undergoing The present progressive tense is for an ongoing action in the present.	have undergone have undergone has undergone have undergone have undergone have undergone The present perfect tense is for an action that began in the past. (Often, the action continues into the present.)	have been undergoing have been undergoing has been undergoing have been undergoing have been undergoing have been undergoing The present perfect progressive tense is for a continuous activity that began in the past and continues into the present (or finished very recently).

Future Tenses

Person	Simple Future	Future Progressive Tense	Future Perfect Tense	Future Perfect Progressive Tense
I you he/she/it we you they	will undergo will undergo will undergo will undergo will undergo will undergo The simple future tense is for an action that will occur in the future.	will be undergoing will be undergoing will be undergoing will be undergoing will be undergoing will be undergoing The future progressive tense is for an ongoing action that will occur in the future.	will have undergone will have undergone will have undergone will have undergone will have undergone will have undergone The future perfect tense is for an action that will have been completed at some point in the future.	will have been undergoing will have been undergoing will have been undergoing will have been undergoing will have been undergoing will have been undergoing The future perfect progressive tense is for an ongoing action that will be completed at some specified time in the future.