This is the 1420th most frequent Russian word.
группе
The word "группе" in Russian is the dative or prepositional case of "группа," meaning "group" in English.
The word 'группе' is used here in the dative case, as the preposition 'к' requires the dative case in Russian to express direction towards the object, in this case, the group.
Я присоединился к группе по интересам.
I joined an interest group.
In this sentence, 'группе' appears in the dative case again, as it is the indirect object of the action 'помочь', which requires the dative case.
Мы решили помочь этой группе добровольцев.
We decided to help this group of volunteers.
Here, 'группе' is in the dative case because it is the indirect recipient of the information, following the preposition 'о', which requires the dative case when expressing a notion to inform or address.