健忘[kenbou] forgetfulness
健忘症[kenboushou] amnesia
度忘[dowasure] lapse of memory
胴忘[douwasure] lapse of memory
年忘れ[toshiwasure] year-end drinking party

備忘[bibou] reminder
備忘録[bibouroku] notebook
忘る[wasuru] to lose something
忘れっぽい[wasureppoi] forgetful
忘れる[wasureru] to forget

あっと言う間に[attoiumani] just like that
からと言って[karatoitte] while it may be true that
斯う言う[kouiu] such
して言えば[shiteieba] if I must say (choose)
ずばずば言う[zubazubaiu] to speak one's mind

そうかと言って[soukatoitte] but still
だからと言って[dakaratoitte] while it may be true that
と言うのは[toiunoha] means
と言う物[toiumono] something like ...
とも言う[tomoiu] also called