Present
| I | challenge |
| You | challenge |
| She | challenges |
| We | challenge |
| They | challenge |
Past
| I | challenged |
| You | challenged |
| She | challenged |
| We | challenged |
| They | challenged |
Perfect
| I | have | challenged |
| You | have | challenged |
| She | has | challenged |
| We | have | challenged |
| They | have | challenged |
Future
| I | will | challenge |
| You | will | challenge |
| She | will | challenge |
| We | will | challenge |
| They | will | challenge |
Past Perfect
| I | had | challenged |
| You | had | challenged |
| She | had | challenged |
| We | had | challenged |
| They | had | challenged |
Future Perfect
| I | will | have | challenged |
| You | will | have | challenged |
| She | will | have | challenged |
| We | will | have | challenged |
| They | will | have | challenged |
Present - Conditional
| I | would | challenge |
| You | would | challenge |
| She | would | challenge |
| We | would | challenge |
| They | would | challenge |
Perfect - Conditional
| I | would | have | challenged |
| You | would | have | challenged |
| She | would | have | challenged |
| We | would | have | challenged |
| They | would | have | challenged |