表兄告诉我：每逢端午节期间，九龙江的北溪、西溪和南溪都要举行龙舟竞赛活动。
B-Person I-Person O O B-Person O O O B-Time I-Time I-Time I-Time I-Time O B-Location I-Location I-Location O B-Location I-Location O B-Location I-Location O B-Location I-Location O O O O B-Thing I-Thing O O O O O