PHP 224, 218, 210 206
foreach(explode(",","I19SR,9ZY8H,,CNK,5JRU0,H,CN4,G0H,H160,CN4,75,CU9,AMIHD,MTQP,HQOXK,7L,74,G,CXS,CU9,HTOG,,CNK,MHA8,CNL,1")as$a){$b++;for($c=0;$c<26;$c++)echo base_convert($a,36,10)&pow(2,$c)?chr(96+$b).chr(97+$c)." ":"";}
aa ab ad ae ag ah ai al am an ar as at aw ax ay ba be bi bo by de do ed ef eh el em en er es et ex fa fe go ha he hi hm ho id if in is it jo ka ki la li lo ma me mi mm mo mu my na ne no nu od oe of oh oi om on op or os ow ox oy pa pe pi qi re sh si so ta ti to uh um un up us ut we wo xi xu ya ye yo za
Definitely not a great score, but I liked the challenge.
I create a table of the options, created a bitwise system to flag which options are valid.
Then I base-36 encoded those options to get the string:
"I19SR,9ZY8H,,CNK,5JRU0,H,CN4,G0H,H160,CN4,75,CU9,AMIHD,MTQP,HQOXK,7L,74,G,CXS,CU9,HTOG,,CNK,MHA8,CNL,1"
Note the 3rd entry in that string array doesn't have a value, because C has no options.
To print the values, I just convert the valid options to chars.
There might be something I could do to reduce recognising that there are no words ending in C, J, K, Q, V or Z, but I can't think of a method to reduce it atm.
By transposing the table, there are more empty elements and the data encodes a little more compactly which shaved off a few bytes. The array is now printed in a different order:
foreach(explode(",","UB1YB,1,,CUP,CLMEJ,CUO,1,SG0H,5J9MR,,,H,MX01,MTXT,CYO5M,MTQ8,,CNL,MTXT,MHAP,50268,,CN5,CNL,FSZ,,")as$a){$b++;for($c=0;$c<26;$c++)echo base_convert($a,36,10)&pow(2,$c)?chr(97+$c).chr(96+$b)." ":"";}
aa ba fa ha ka la ma na pa ta ya za ab ad ed id od ae be de fe he me ne oe pe re we ye ef if of ag ah eh oh sh uh ai bi hi ki li mi oi pi qi si ti xi al el am em hm mm om um an en in on un bo do go ho jo lo mo no so to wo yo op up ar er or as es is os us at et it ut mu nu xu aw ow ax ex ox ay by my oy
Thanks to Ismael for the explode and for loop hints.
foreach(explode(3,UB1YB3133CUP3CLMEJ3CUO313SG0H35J9MR333H3MX013MTXT3CYO5M3MTQ833CNL3MTXT3MHAP35026833CN53CNL3FSZ)as$d)for($e++,$f=0;$f<26;$f++)echo base_convert($d,36,10)&pow(2,$f)?chr(97+$f).chr(96+$e)." ":"";
With an update to php5.6, pow(,)
can be replaced by **
saving another 4 bytes.
foreach(explode(3,UB1YB3133CUP3CLMEJ3CUO313SG0H35J9MR333H3MX013MTXT3CYO5M3MTQ833CNL3MTXT3MHAP35026833CN53CNL3FSZ)as$d)for($e++,$f=0;$f<26;$f++)echo base_convert($d,36,10)&2**$f?chr(97+$f).chr(96+$e)." ":"";