What part of speech is conduct?

"Conducting" is the present participle or gerund form of the verb "conduct". As a participle, it usually functions in a sentence as an adjective, although it can also be a verb as part of a progressive tense that requires more than one Word to express, as in the sentence, "Arturo Toscanini was conducting the New York Philharmonic Orchestra on a night long ago." As a gerund, by definition, "conducting" functions as a noun, often with some other Words that form a noun phrase, as in, "Conducting a major orchestra is a challenging activity." In this sentence, the noun clause, "Conducting a major orchestra", is the subject of the sentence.