2d is an anagram of naval shipyard minus pansy and the defn is a sergeant
3d hollow is the defn. 3 letter tree ,(starts with a!) not sure how the next 3 letters fit the wordplay
11a defn cheese. French word for wine with "a sherry" inside
17a it device is the defn. 4 letters for quality + 3 letter word for flat(accomodation)
Good luck - I've finished but it was a mighty struggle!