{HEAD ~ at least a part} of {TAIL ~ the first element} is closer to the front surface than the second element is to the front surface 
of
{ HEAD ~ at least a part } of { TAIL ~ the first element } is closer to the front surface than the second element is to the front surface
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH