Develops (7)
(Other definitions for becomes that I've seen before include "Turns into" , "Changes into" , "Suits, befits" , "Gets" , "Undergoes a change" .)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">develops</span>' is the definition.<br/ ><span class="explanation-format__explanation">('evolve' can be a synonym of 'develop')</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for evolves that I've seen before include "Develops gradually, perhaps over millennia" , "is on the increase" , "Develops by degrees" , "Gradually develops into over time" .)