options: m : all right , thanks ! i 'm on the first floor . i 'll go upstairs . m : thank you . i see the laboratory at the corner . it 's on the first floor . m : so you mean that the laboratory is on the third floor ? m : since i 'm already on the second floor , i can go to the laboratory .
article: m : i 'm looking for the laboratory . am i on the right floor ? f : no , it 's on the second floor . you can take the stair up .