| I | undergo |
|---|---|
| you | undergo |
| he/she/it | undergoes |
| we | undergo |
| you | undergo |
| they | undergo |
| I | underwent |
|---|---|
| you | underwent |
| he/she/it | underwent |
| we | underwent |
| you | underwent |
| they | underwent |
| I | have | undergone |
|---|---|---|
| you | have | undergone |
| he/she/it | has | undergone |
| we | have | undergone |
| you | have | undergone |
| they | have | undergone |
| I | had | undergone |
|---|---|---|
| you | had | undergone |
| he/she/it | had | undergone |
| we | had | undergone |
| you | had | undergone |
| they | had | undergone |
单语范例（未经PONS编辑处理）
Some time later, the program has undergone more changes.
en.wikipedia.org Its three carboxylic acid groups undergo deprotonation upon complexation.
en.wikipedia.org Today, the road over the dam is still in use and is undergoing major upgrades.
en.wikipedia.org The resulting o-benzoylbenzoic acid then undergoes cyclization, forming anthraquinone.
en.wikipedia.org Characters have undergone something of a revival with the launching of webcomic in 2006.
en.wikipedia.org