| in a pig's patoot |
| in a pinch |
| in a rut |
| in a snap |
| in a walk |
| in bad odor |
| in bed |
| in black and white |
| inch along |
| in character |
| inch by inch |
| inch forward |
| inch up |
| inchworm |
| in concert |
| in control |
| Indian sign |
| in diapers |
| in droves |
| in Dutch |
| I never miss |
| in every sense of the word |
| in fighting trim |
| in focus |
| in for a penny, in for a pound |
| in for it |
| in full force |
| in full gear |
| in harness |
| in heaven's name |
| in hot pursuit |
| in jest |
| in kind |
| in layman's terms |
| in light of |
| in line |
| inner ear |
| inner strength |
| in nothing flat |
| in no time |
| in on |
| in one bite |
| in one's altitudes |
| in one's back pocket |
| in one's cups |
| in one's dreams |
| in one's own good time |
| in one's own little way |
| in one's wildest dreams |
| in order |
| in pampers |
| in plain sight |
| in reaction |
| in recent memory |
| in safe hands |
| ins and outs |
| in short trousers |
| inside baseball |
| inside out |
| inside scoop |
| in someone's face |
| in someone's pocket |
| in spades |
| in spite of |
| installed base |
| in stitches |
| interpret away |
| in the act |
| in the black |
| in the blink of an eye |
| in the business of |
| in the can |
| in the dock |
| in the driving seat |
| in the flower of one's youth |
| in the green tree … in the dry |
| in the hopper |
| in the know |
| in the line of duty |
| in the making |
| in the offing |
| in the raw |
| in the right place at the right time |
| in the same boat |
| in the snap of one's fingers |
| in the stratosphere |
| in the tank |
| in the trenches |
| in the way of |
| in the world |
| in this day and age |
| in token of |
| into thin air |
| in two shakes of a lamb's tail |
| invited to the cookout |
| in your dreams |
| iron fist |
| I see, said the blind man |
| itch the ditch |
| I tell you |