Solutions :

3-letter words (1 point): 42

EFT; ELF; ELL; ELT; FEN; FIE; FIL; FIN; FIR; FIT; FON; FOP; FOU; ILL; IRE; LEI; LIE; LIT; NEF; NIE; NOT; OFT; OIL; ONE; OPT; ORE; OUP; OUT; POT; PUT; REI; RIF; RIT; TIE; TIL; TON; TOP; TUI; TUP; UPO; VIE; VOR.

4-letter words (1 point): 60

FELL; FELT; FENI; FENT; FIER; FILE; FILL; FINE; FINO; FIRE; FLIR; FLIT; FONE; FONT; INFO; INTI; INTO; LEFT; LEIR; LENO; LENT; LIER; LIFE; LIFT; LIRE; LITU; NEIF; NIEF; NIFE; NOUP; NOUT; ONIE; ORLE; PONE; PONT; POUT; PTUI; PUIR; REIF; RIEL; RIFE; RIFT; RILE; RILL; RIVO; ROIL; TIER; TILE; TILL; TIRE; TIRL; TIRO; TONE; UPON; VIER; VILE; VILL; VIRE; VIRL; VRIL.

5-letter words (2 points): 24

ELFIN; ERVIL; FEINT; FIENT; FILER; FILLE; FLIER; ILLER; INTIL; LENTI; LENTO; LIVOR; LIVRE; OILER; ORIEL; PUTON; RELIT; RIFLE; RILLE; TILER; UPTIE; UTILE; VILER; VOILE.

6-letter words (3 points): 20

ENFIRE; ENTIRE; FELLER; FILLER; INFELT; INFILL; INTIRE; LEFTIE; LENTIL; NELLIE; NIELLI; OUTLER; OUTLIE; OUTVIE; PONTIE; PONTIL; RELENT; TILLER; TUILLE; VIELLE.

7-letter words (7 points): 8

FELTIER; NIFTIER; OUTFIRE; OUTLIER; PONTILE; POUTIER; RELLENO; VILLEIN.