| singular | plural |
| Infinitive | | |
| undo | |
| present simple | | |
| 1 | I undo | we undo |
| 2 | you undo | you undo |
| 3 | he/she/it undoes | they undo |
| past simple | | |
| 1 | I undid | we undid |
| 2 | you undid | you undid |
| 3 | he/she/it undid | they undid |
| future simple | | |
| 1 | I will/shall undo | we will/shall undo |
| 2 | you will/shall undo | you will/shall undo |
| 3 | he/she/it will/shall undo | they will/shall undo |
| conditional simple | | |
| 1 | I would undo | we would undo |
| 2 | you would undo | you would undo |
| 3 | he/she/it would undo | they would undo |
| present continuous | | |
| 1 | I am undoing | we are undoing |
| 2 | you are undoing | you are undoing |
| 3 | he/she/it is undoing | they are undoing |
| past continuous | | |
| 1 | I was undoing | we were undoing |
| 2 | you were undoing | you were undoing |
| 3 | he/she/it was undoing | they were undoing |
| future continuous | | |
| 1 | I will be undoing | we will be undoing |
| 2 | you will be undoing | you will be undoing |
| 3 | he/she/it will be undoing | they will be undoing |
| conditional continuous | | |
| 1 | I would be undoing | we would be undoing |
| 2 | you would be undoing | you would be undoing |
| 3 | he/she/it would be undoing | they would be undoing |
| present perfect | | |
| 1 | I have undone | we have undone |
| 2 | you have undone | you have undone |
| 3 | he/she/it has undone | they have undone |
| past perfect | | |
| 1 | I had undone | we had undone |
| 2 | you had undone | you had undone |
| 3 | he/she/it had undone | they had undone |
| future perfect | | |
| 1 | I will have undone | we will have undone |
| 2 | you will have undone | you will have undone |
| 3 | he/she/it will have undone | they will have undone |
| conditional perfect | | |
| 1 | I would have undone | we would have undone |
| 2 | you would have undone | you would have undone |
| 3 | he/she/it would have undone | they would have undone |
