<span class="searchmatch">diffūdissem</span> first-person singular pluperfect active subjunctive of diffundō...
diffūderīs diffūderit diffūderīmus diffūderītis diffūderint pluperfect <span class="searchmatch">diffūdissem</span> diffūdissēs diffūdisset diffūdissēmus diffūdissētis diffūdissent passive...