Be acquainted with (4)
I believe the answer is:
know
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">be acquainted with</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 know that I've seen before include "Recognize" , "Be sure of something" , "Be aware of (something)" , "Have information" , "Articulated" .)