H connects "how" to "much" or "many". "Much" and "many" can serve as determiners ("How many books do you have"); they can also serve as independent noun-phrases ("How many do you have"). Unlike most determiners, they can also be preceded by the word "how" in either case, creating a question or indirect question:
+--H-+-Dmc-+ | | | How many books do you haveTherefore they have H- connectors, optionally conjoined with their D+ connectors and also with their main noun complexes. However: when the H- is being used on "many" and "much", a question situation is created (direct or indirect). This introduces constraints on word-order, mainly relating to subject-verb inversion. For this reason, H+ on "how" is conjoined with QI- (used in indirect questions) or Wq- or Ws- (used in direct questions). These connectors trigger post-processing rules; see SI. H is also in a post-processing category along with D##w, relating also to s-v inversion; see "SI: Questions without s-v inversion".
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