ratel artel rtael trael atrel tarel raetl aretl reatl eratl aertl eartl rteal treal retal ertal teral etral aterl taerl aetrl eatrl tearl etarl ratle artle rtale trale atrle tarle ralte arlte rlate lrate alrte larte rtlae trlae rltae lrtae tlrae ltrae atlre talre altre latre tlare ltare raelt arelt realt eralt aerlt earlt ralet arlet rlaet lraet alret laret relat erlat rleat lreat elrat lerat aelrt ealrt alert laert elart leart rtela trela retla ertla terla etrla rtlea trlea rltea lrtea tlrea ltrea relta erlta rleta lreta elrta lerta telra etlra tlera ltera eltra letra atelr taelr aetlr eatlr tealr etalr atler taler alter later tlaer ltaer aeltr ealtr aletr laetr elatr leatr telar etlar tlear ltear eltar letar
Note: these 'words' (valid or invalid) are all the permutations of the word ratel. These words are obtained by scrambling the letters in ratel.