This is the 666th most frequent German word.
sprechen
To speak.
Here, 'sprechen' is used in the context of indicating a skill or language that the subject possesses or uses.
Ich spreche Deutsch.
I speak German.
In this sentence, 'sprechen' conveys the act of verbal communication planned to occur in the future, with 'mit' indicating the person being spoken to.
Er wird morgen mit ihr sprechen.
He will speak with her tomorrow.
'Sprechen' here is used to describe discussing or conversing about a specific topic indicated by the preposition 'über'.