| Present "mumble" | I | mumble | |
| Present Continuous "mumble" | I | am mumbling | |
| Simple past "mumble" | I | mumbled | |
| Past Continuous "mumble" | I | was mumbling | |
| Present perfect "mumble" | I | have mumbled | |
| Present perfect continuous "mumble" | I | have been mumbling | |
| Past perfect "mumble" | I | had mumbled | |
| Past perfect continuous "mumble" | I | had been mumbling | |
| Future "mumble" | I | will mumble | |
| Future continuous "mumble" | I | will be mumbling | |
| Future perfect "mumble" | I | will have mumbled | |
| Future perfect continuous "mumble" | I | will have been mumbling |