Prolong (7)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">prolong</span>' is the definition.<br/ ><span class="explanation-format__explanation">(thesaurus)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for stretch that I've seen before include "Bit of exercise" , "Make to go further" , "Exercise - period" , "Make (something) longer" , "sort of limousine" .)
(Other definitions for sustain that I've seen before include "Carry" , "Provide nourishment" , "Support, keep going" , "Bear (something's weight)" , "Nurish" .)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">prolong</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I know that extend is a type of prolong)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for extend that I've seen before include "Stretch out over a distance or lengthen in time" , "Reach out, say the hand of friendship" , "Draw out" , "make offer?" , "Reach out or stretch" .)