How about these proposals?
"spit", "spat" (past tense), "sput" (past participle)
"move", "moved" (past tense), "moven" (past participle) (cf. "proven")
"spit", "spat" (past tense), "sput" (past participle)
"move", "moved" (past tense), "moven" (past participle) (cf. "proven")