Present
| I | doubt |
| You | doubt |
| She | doubts |
| We | doubt |
| They | doubt |
Past
| I | doubted |
| You | doubted |
| She | doubted |
| We | doubted |
| They | doubted |
Perfect
| I | have | doubted |
| You | have | doubted |
| She | has | doubted |
| We | have | doubted |
| They | have | doubted |
Future
| I | will | doubt |
| You | will | doubt |
| She | will | doubt |
| We | will | doubt |
| They | will | doubt |
Past Perfect
| I | had | doubted |
| You | had | doubted |
| She | had | doubted |
| We | had | doubted |
| They | had | doubted |
Future Perfect
| I | will | have | doubted |
| You | will | have | doubted |
| She | will | have | doubted |
| We | will | have | doubted |
| They | will | have | doubted |
Present - Conditional
| I | would | doubt |
| You | would | doubt |
| She | would | doubt |
| We | would | doubt |
| They | would | doubt |
Perfect - Conditional
| I | would | have | doubted |
| You | would | have | doubted |
| She | would | have | doubted |
| We | would | have | doubted |
| They | would | have | doubted |