What should the one who has not learned the supplications in the funeral prayer do?

Imâm Sâlih bin Fawzân al-Fawzân

Question: If someone has not learned supplications reported in the Sunnah for the deceased, can he just supplicate for him to be forgiven?

Answer: Yes, he can limit himself to what he knows. It is not unknown to anyone how to supplicate for forgiveness and mercy for the deceased. Everyone knows that. Ask Allâh to have mercy on him, to forgive him and to save him from the Hellfire – as you supplicate for yourself.