I know in English and German that neither two seem to have a 1:1 translation all the time, so it's better now for me to ask why certain ideas are expressed in certain ways in German.
To ask the question Do you agree with him? in English, I need the word "with" to complete the sentence (a preposition)
but in German, I want to understand why we don't need such a preposition
Stimmst du ihm zu?
I know that "ihm" is the object that the verb "zustimmen" relates to, and the "zu" is just relevant to the fact that the verb "zustimmen" is separable, but why in German do we not convey a preposition?
Is it assumed or just not used in "syntax"?