In [1]:
s = 'The/DET Dog/NN is/VB fast/JJ ./.'
In [3]:
pairs = [p.split('/') for p in s.split()]
print pairs
[['The', 'DET'], ['Dog', 'NN'], ['is', 'VB'], ['fast', 'JJ'], ['.', '.']]

In [7]:
for p in pairs:
    print '<word ortho="%s" pos="%s"></word>' % (p[0], p[1])
<word ortho="The" pos="DET"></word>
<word ortho="Dog" pos="NN"></word>
<word ortho="is" pos="VB"></word>
<word ortho="fast" pos="JJ"></word>
<word ortho="." pos="."></word>