Excited about (4)
I believe the answer is:
into
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">excited about</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for into that I've seen before include "Four this twelve is three" , "Fascinated by" , "Showing enthusiasm for" , "Keenly interested in" , "Not I (anag.)" .)