Question

the meeting has been going on dash four hour now

Answer 1

"The meeting has been going on for four hours now. For are a preposition and conjunction depending on how it is used? However, in some circumstances, it might not be appropriate.

A preposition is a term such as after, in, too, on, and with. 

Prepositions are ordinarily used at the beginning of nouns or pronouns, and they determine the relation among the noun or pronoun and another word in order.

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