Sorry: forget the Past Participle bit -- it's the infinitive of course (have no copy, had to send off hours ago)
22: 3rd letter is R, correct!
And in general: all 12 are well hidden! As I explained on the older thread, I was lost for ages though I had nearly everything correct,having overlooked the instruction completely (!!!), and even then some of the 12 you just don't notice at first!