Constraining passive participles

grammars ERG
1

I asked this question previously in a thread with multiple questions, so to make each thread address only one topic I’m reposting it as multiple threads.

I have an MRS I want to use to generate strings like “the locked car, west of the green bush.”

Here is the MRS:

[ TOP: h19                                                                       
   INDEX: x1                                                                      
   RELS: < [ loc_nonsp LBL: h19 ARG0: i16 ARG1: x1 ARG2: x13 ]                    
           [ def_implicit_q LBL: h30 ARG0: x13 RSTR: h28 BODY: h29 ]              
           [ _west_a_1 LBL: h15 ARG0: i12 ARG1: x13 ARG2: x22 ]                   
           [ def_udef_a_q LBL: h25 ARG0: x22 RSTR: h23 BODY: h24 ]                
           [ _green_a_2 LBL: h11 ARG0: i9 ARG1: x22 ]                             
           [ _bush_n_1 LBL: h11 ARG0: x22 ]                                       
           [ place_n LBL: h15 ARG0: x13 ]                                         
           [ _lock_v_cause LBL: h19 ARG0: e3 ARG1: i4 ARG2: x1 ]                  
          [ _car_n_1 LBL: h19 ARG0: x1 ] >                                       
   HCONS: < h23 qeq h11 h28 qeq h15 > ]

In addition to the strings I want, I am also getting things like the following:

The car locked west of the green bush  
The car to lock west of the green bush  
The car west of the green bush locked  
The car west of the green bush to lock

  1. Is there a way to eliminate the “to lock” ones? I’m hoping there’s some tense constraint I can use.

  2. Is there a way to prevent the modifier of car from moving after it? This seems to be similar to the issue I was having with the MRS in the previous example

2

Dan answered this question in the other thread, which I will paste here:

On your second topic, constraining passive participles, I think we can do a little better, though the solution is only partly theoretically sound. Since the passive lexical rule has an information-structure effect, there is an ICONS “topic” constraint linking the index of the passivized object with the event of the verb, so when you add this constraint to the input MRS for the generator, you’ll only see passive relative clauses, not the infinitival ones. So in your MRS for “the locked car …” you can add this line after the HCONS constraints;

ICONS: < e3 topic x1 >

where “e3” is the ARG0 of the “lock” EP and “x1” is the ARG2 of that EP. With this added constraint, you won’t generate “the car to lock”.

In order to also block generation of “the car locked”, we have to resort to a less satisfying solution which takes advantage of a slight difference in the MRSs of “locked car” and “car locked”, namely that the grammar constrains the aspect of the ARG0 of “locked” when it’s pre-nominal to be [PERF -] (non-perfect), but for no deep reason fails to assert this of “locked” when it’s a post-nominal modifier. So if you add [PERF -] to that ARG0 in your MRS input to the generator, you won’t get the output “car locked” because the generator has to produce an output which accounts for every element of the input MRS, and the generated structure for “car locked” won’t say anything about the value of PERF for the ARG0 of “lock”. That is, in your example MRS, the EP for lock_v_cause should read

[ _lock_v_cause LBL: h19 ARG0: e3 [e PERF: -] ARG1: i4 ARG2: x1 ]

With these two additions to the MRS you started with, you should see the behavior you want. for passive participles. Note that while “the car locked” doesn’t sound great, this post-modifier structure is not infrequent, as you see in examples such as “the papers rejected were still of good quality” and “the topics discussed cover a wide range of concerns”. I don’t yet have an account of how the unhappy “car locked” is different from the fine “topics discussed”, so the grammar doesn’t distinguish them.