Kev siv lub qhov rooj steel hlau mus ntev yuav tsis ua rau muaj teeb meem zoo vim yog qhov qhib thiab kaw. Ntoo qhov rooj hluav taws yeej tsis muaj hluav taws kub zoo li cov hlau, yog li thaum lub qhov rooj hluav taws kub tshwm sim hauv khw, lawv sai sai dhau los ua lub hauv paus ntawm kev ua lag luam.

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