In the main (7)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">in the main</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for largely that I've seen before include "Generally" , "Mainly" , "To a great extent" , "to a considerable extent" , "Fro the most part" .)
(Other definitions for marine that I've seen before include "Oceanic" , "Maritime - seagoing soldier" , "Soldier associated with a navy" , "Soldier-sailor" , "Member of the forces" .)