Present
| I | lack |
| You | lack |
| She | lacks |
| We | lack |
| They | lack |
Past
| I | lacked |
| You | lacked |
| She | lacked |
| We | lacked |
| They | lacked |
Perfect
| I | have | lacked |
| You | have | lacked |
| She | has | lacked |
| We | have | lacked |
| They | have | lacked |
Future
| I | will | lack |
| You | will | lack |
| She | will | lack |
| We | will | lack |
| They | will | lack |
Past Perfect
| I | had | lacked |
| You | had | lacked |
| She | had | lacked |
| We | had | lacked |
| They | had | lacked |
Future Perfect
| I | will | have | lacked |
| You | will | have | lacked |
| She | will | have | lacked |
| We | will | have | lacked |
| They | will | have | lacked |
Present - Conditional
| I | would | lack |
| You | would | lack |
| She | would | lack |
| We | would | lack |
| They | would | lack |
Perfect - Conditional
| I | would | have | lacked |
| You | would | have | lacked |
| She | would | have | lacked |
| We | would | have | lacked |
| They | would | have | lacked |