| Simple | Progressive | Perfect | Progressive |
| Present |
| I stem |
| you stem |
| he/she/it stems |
| we stem |
| you all stem |
| they stem |
|
| I am stemming |
| you are stemming |
| he/she/it is stemming |
| we are stemming |
| you all are stemming |
| they are stemming |
|
| I have stemmed |
| you have stemmed |
| he/she/it has stemmed |
| we have stemmed |
| you all have stemmed |
| they have stemmed |
|
| I have been stemming |
| you have been stemming |
| he/she/it has been stemming |
| we have been stemming |
| you all have been stemming |
| they have been stemming |
|
| Past |
| I stemmed |
| you stemmed |
| he/she/it stemmed |
| we stemmed |
| you all stemmed |
| they stemmed |
|
| I was stemming |
| you were stemming |
| he/she/it was stemming |
| we were stemming |
| you all were stemming |
| they were stemming |
|
| I had stemmed |
| you had stemmed |
| he/she/it had stemmed |
| we had stemmed |
| you all had stemmed |
| they had stemmed |
|
| I had been stemming |
| you had been stemming |
| he/she/it had been stemming |
| we had been stemming |
| you all had been stemming |
| they had been stemming |
|
| Future |
| I will stem |
| you will stem |
| he/she/it will stem |
| we will stem |
| you all will stem |
| they will stem |
|
| I will be stemming |
| you will be stemming |
| he/she/it will be stemming |
| we are stemming |
| you all will be stemming |
| they will be stemming |
|
| I will have stemmed |
| you will have stemmed |
| he/she/it will have stemmed |
| we will have stemmed |
| you all will have stemmed |
| they will have stemmed |
|
| I will have been stemming |
| you will have been stemming |
| he/she/it will have been stemming |
| we will have been stemming |
| you all will have been stemming |
| they will have been stemming |
|
