電話するの を 忘れて ごめん なさい。denwasuruno wo wasurete gomen nasai.
Please forgive me for forgetting to call you.
Sentence from Tatoeba
Note
Sentence from TatoebaBreakdown of denwasuruno wo wasurete gomen nasai.
をwo
direct object particle
電話するdenwasuru
to call, to telephone
忘れるwasureru
to forget
