| In this vicinity | 16 |
| In this way | 11 |
| In this world | 13 |
| In this, a "." is a "dot" | 45 |
| In this, a "." is a "period" | 48 |
| In this, a "." is a "point" | 47 |
| In this, following directions is mandatory | 42 |
| In those days | 13 |
| In those days (with "back") | 37 |
| In threads | 10 |
| In three divisions | 18 |
| In three parts | 14 |
| In three sections | 17 |
| In tidy condition | 17 |
| In tiers | 8 |
| In tight curls | 14 |
| In time | 7 |
| In time gone by | 15 |
| In time past | 12 |
| In time past, in time past | 26 |
| In time, musically | 18 |
| In time, to Ozawa | 17 |
| In time: Music | 14 |
| In times past | 13 |
| In times ___ | 12 |
| In tiny pieces | 14 |
| In tip-top shape | 16 |
| In tiptop shape | 15 |
| In to the maximum extent | 24 |
| In too deep? | 12 |
| In top form | 11 |
| In total | 8 |
| In total accord | 15 |
| In total agreement (with) | 25 |
| In toto | 7 |
| In touch with who one is | 24 |
| In tow | 6 |
| In town | 7 |
| In traffic, say | 15 |
| In transit | 10 |
| In transit, maybe | 17 |
| In tribute to | 13 |
| In trig, sine's reciprocal | 30 |
| In trig, the reciprocal of sin | 30 |
| In trim | 7 |
| In triplicate, a Seinfeld catchphrase | 37 |
| In trouble | 10 |
| In trouble for being baseless? | 30 |
| In trouble, in slang | 20 |
| In trouble, in the Army | 23 |
| In trouble, with "off" | 32 |
| In trustworthy fashion | 22 |
| In truth | 8 |
| In truth, in Shakespeare | 24 |
| In truth, old-style | 19 |
| In tune | 7 |
| In tune with current events | 27 |
| In Turkey, 100 piasters | 23 |
| In turmoil | 10 |
| In two | 6 |
| In two different places | 23 |
| In two parts | 12 |
| In two pieces, like two-by-fours | 32 |
| In two pieces, maybe | 20 |
| In two places | 13 |
| In two places at once? | 22 |
| In two shakes | 13 |
| In two ways | 11 |
| In two, say | 11 |
| In two: Comb. form | 18 |
| In type | 7 |
| In typical fashion | 18 |
| In uncharted territory, so to speak | 35 |
| In under the tag | 16 |
| In underhanded fashion | 22 |
| In unfamiliar territory | 23 |
| In unfamiliar territory, maybe | 30 |
| In unison | 9 |
| In unison with as | 18 |
| In unison, at the Met | 21 |
| In unison, in a way | 19 |
| In unison, in music | 19 |
| In unison, in scores | 20 |
| In unison, musically | 20 |
| In unison, on a score | 21 |
| In unison, on scores | 20 |
| In unison: Mus. | 15 |
| In unkind style | 15 |
| In unruffled style | 18 |
| In up to one's neck | 23 |
| In UPS's hands | 18 |
| In use | 6 |
| In use, as a phone line | 23 |
| In use, as an apartment building | 32 |
| In utero | 8 |
| In utero surgery site | 21 |
| In utter confusion | 18 |
| In vain | 7 |
| In various places | 17 |
| In various spots | 16 |