Here is the complete group of real words you can form with the letters in FIRST, displayed in a straightforward format for easy confirmation.
Words You Can Make from FIRST
3-letter words
- FIR6
- FIT6
- IFS6
- ITS3
- RIF6
- SIR3
- SIT3
- SRI3
- TIS3
4-letter words
- FIRS7
- FIST7
- FITS7
- FRIT7
- RIFT7
- SIFT7
- STIR4
5-letter words
- FIRST8
- RIFTS8
The list above includes all words you can make from FIRST using its letter set. The final total is 18 valid words.