def transpose_two_strings(arr):
    
    spis1, spis2 = arr[0], arr[1]
    maxlen = max(len(spis1), len(spis2))
    result = []

    for i in range(maxlen):
        sim1 = spis1[i] if i < len(spis1) else ' '
        sim2 = spis2[i] if i < len(spis2) else ' '
        result.append(f"{sim1} {sim2}")

    return '\n'.join(result)