Swot (3,2)
I believe the answer is:
mug up
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">swot</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I know that swot can be written as mug up)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for mug up that I've seen before include "Study quickly (for, eg, an exam)" , "Swot hard" , "Learn quickly (for exam)" , "Quickly revise" , "Revise for an exam" .)