Letters that make unprogressive
s, o, e, g, n, p, r, i, u, v are letters that make 'unprogressive'
Words within unprogressive
RES, re, si, PR, UN, NP, Ro, SI, SS, progressive, pro, iv, progress, IV, ogre, ogress, Re, Es, Np, Pr, Si are words within 'unprogressive'