DIRECTIONS for the question: Read the sentence to find out whether there is any grammatical error or idiomatic error in it. The error, if any, will be in one part of the sentence. The number of that part is the answer. if there is 'No Error" the answer is (E). (Ignore errors of punctuation if any.)
My uncle, who was on vacation, along with my two cousins and I, went fishing down by the river. No error.