This is the 9239th most frequent Russian word.
соединяла
"Соединяла" means "was connecting" or "joined" in English.
Here, "соединяла" is used in the literal sense, describing the act of physically joining wires together.
Она соединяла провода, чтобы восстановить электричество.
She connected the wires to restore electricity.
In this sentence, "соединяла" indicates the function of the road as a link or connection between two cities.
Эта дорога соединяла два города много лет назад.
This road connected two cities many years ago.
Here, "соединяла" is used metaphorically, describing the act of integrating knowledge for teaching purposes.