Letters that make negative reinforcer
a, o, e, f, g, n, c, r, t, i, v are letters that make 'negative reinforcer'
Words within negative reinforcer
ER, gat, OR, rein, CER, reinforcer, info, re, ti, FO, at, negative, iv, CE, in, force, IV, IN, NE, Re, reinforce, At, Ce, Er, Ga, In, Ne, Ti, GA are words within 'negative reinforcer'