(1) The word 'sail' appears in the poem in lines like 'Boats sail on the rivers' and 'ships sail on the seas.' (2) The word 'river' appears in the poem in the line 'Boats sail on the rivers' and 'There are bridges on the rivers.' (3) The word 'sea' appears in the poem in the line 'And ships sail on the seas.' (4) The word 'clouds' appears in the poem in the line 'But clouds that sail across the sky.' (5) The word 'bridges' appears in the poem in the line 'There are bridges on the rivers.' (6) The word 'heaven' appears in the poem in the line 'But the bow that bridges heaven.' (7) The word 'overtops' appears in the poem in the line 'And overtops the trees.' (8) The word 'bow' appears in the poem in the line 'But the bow that bridges heaven.' (9) The word 'road' appears in the poem in the line 'And builds a road from earth to sky.'