I've seen it quite many times but it sounds like it repeats same thing twice?
2 Answers
No, "to take part to join us" is not a valid sentence. A group of words lacking a subject and predicate is a phrase, not a sentence. If you intended to ask whether or not "To take part is to join us" is a valid sentence, then the answer is yes. Grammatically speaking, "To take part" is an infinitive phrase functioning as the subject, and "to join us" is an infinitive phrase functioning as a predicate noun following "is," the linking verb. You are correct though, it sounds somewhat nonsensical, but also like something a teacher may say on occasion to an errant child. There's a better way to express the same idea; try this: "Participating means joining us."
It should be like this : to take part for joining us.
