In Hausa,one of the main discourse status markers is the definiteness suffix.  Its form is -`n/-`r~/-`n (m/f/pl), . is used to mark an object that is known. Usually, the first time an object is mentioned, it will appear without the definiteness marker, but it can be optionally used on all later mentions of the item.  To deal with this, I made three rules (for m/f/pl) which added the correct suffix as well as added a COG-ST uniq+fam+act.

Hausa has demonstrative determiners, as well as demonstrative pronouns. I did not include demonstrative pronouns in my test suite, so I am mainly focusing on demonstrative determiners(wata, "this.fem" and wani "this.masc).  I hope to add demonstrative pronouns later on.  Demonstrative pronouns are split by m/f/non-sg, and include this(by me), that(by you), that(there), and that (distant).  

I added a demonstrative-determiner-lex type, but I can't get it to work.  I've been having problems with unification between the type and the lexicon.  I'm trying to add the gender and number information in the entries in the lexicon (through SYNSEM.LOCAL.CONT.HOOK.INDEX.PNG), but it says that this doesn't unify with the type constraints.  I'm particularly confused about why the LKB doesn't complain when I put [GEN fem] into the demonstrative-determiner-lex itself, but I can't write a subtype that adds the GEN information (f-demonstrative-lex, see hausa.tdl file, directly under demonstrative-determiner-lex).  I left demonstratives inheriting from determiner-lex, as this gave them the correct behavior (but not the "exist_n_rel" or COG-ST information).    

Hausa has subject pro-drop, in that it requires that pronouns be dropped when they appear as subjects.  This means that the subject is understood by context.  To take care of this I added an instance of basic-head-opt-subj-phrase.  This allows subject-less sentences, such as "taa-zoo", (she-came).  In the last lab I added a PRO feature to distinguish pronouns from other words, and made all nouns PRO -.  I then required verbs to take a PRO + subject.  This took care of making sentences with pronoun subjects ungrammatical (such as "*ita taa-zoo", *she came).

I tested the subject pro-drop with sentences "*ita taa-zoo", "taa-zoo", and transitives "taa-dafà miyàa" and  "*ita taa-dafà miyàa" (she cooked soup).  The grammar was able to give parses for the pronoun-less sentences, and wasn't able to parse the pronoun-subject sentences.  A side issue was pronouns in coordination, which should be able to be subjects.  These are able to work as subjects, though I haven't figured out how to constrain their case to be 'independent'.  In my test sentences I have three cases of pronouns in coordinated subjects, and all three parse right now.

As far as I can tell, Hausa doesn't have optional objects.  There are a few exception, but these seem to be rare enough that I'm not going to cover them.  I can't find the page in my reference grammar, but the example given for these exceptions was something like "my wife, she is doing lunch", when it is understood that she is cooking lunch.  

Adjectives in Hausa appear both before and after their head noun.  When appearing before the noun, they have to take on a linker suffix -n/-r~/-n (m/f/pl).  To cover this, I made an adj-lex-rule which adds POSTHEAD - to an adjective. I also  made three subtype rules for m/f/pl which add gender/number information.  made instances of these three rules in the irules.tdl file to add the correct suffix.  As I have it now, the rule fails to give POSTHEAD- and suffixes to prenominal adjectives.  I think 

For adverbs, I added an adverb-lex rule, and tested it with jiyà "yesterday".  Adverbs in Hausa generally show up at the end of the sentence, after the subject, verb and object (if any) information.  Temporal verbs like jiyà can show up at the beginning of the sentence as well.  I added three examples to my test suite to show adverbs and stacking adverbs (taa-dafà miyàa sòosai jiyà, "she cooked soup perfectly yesterday").  One is ungrammatical, since it appears between the verb and its object.  My grammar overgenerates, since this sentence is parsed as grammatical.

To get the right behavior, I needed to constrain the adjectives to have the same gender and number information as their head noun.  I tried to make a co-reference on the PNG value of the first item of the adjective-lex's mod list, and adjective-lex itself, but I kept getting an error in "unification with ARG1-EV-RELATION at synsem.local.cont.rels.list.first".  To get around this, I made three subtypes m-adjective, f-adjective and pl-adjective which placed gender/number constraint on the MOD value.  I then had my adjectives inherit from the apropriate subtype.  I think it's simpler to do it the first way, but I just couldn't figure out that error, and I wanted to move on to adding a suffix rule for adjectives.

To test the adjectives, I used a sample sentence from my test suite,  "yaaròo k`àramii ya-sàyaa mootàa faraa", lit." the boy small bought a car white".  I used batch parse and tried all four possible orders and combinations for the subject "yaaròo k`àramii", "*k`àramii yaaròo", "k`àramii-n yaaròo" and "*yaaròo k`àramii-n".  The adj+suffix combinations didn't parse, but the other two orders did.  When I tried interactive unification with the adj-head-int rule, it seemed to work.  So in trying to fix this, I'm going to focus on fixing the lexical rule, or the interaction of the two.