This document discusses phrase structure rules in Unification Grammar. It explains that unification grammar uses both phrase structure rules and unification, where unification allows for feature structure sharing. The key points are that phrase structure rules involve mother phrases having daughter phrases, with the mother and head daughter sharing head features. Additionally, if the non-head daughter matches the valence feature of the head daughter, the valence feature is deleted from the mother phrase. Through unification and feature sharing, information about constituents like subject and object are shared in the content feature of verbs.

1. Phrase structure rules in
Unification Grammar

2. Unification Grammar
• Also have Phrase Structure Rules
• PSRs PLUS unification
• Unification and feature structure sharing is the
same thing
• PSRs PLUS unification
• No movement

3. Phrase Structure Rules

4. What’s this?

5. It’s simple

6. Mother phrases have daughters

7. The mother and the HEAD daughter
share the HEAD feature

8. So in a sentence like [she walks] …

9. The phrase is a verb phrase

10. And if the non-head daughter …

11. (in [she walks] the non-head daughter
is [she])

12. If the non-head daughter matches the
VALENCE feature on the head
daughter …

13. Delete the valence feature on the
mother phrase

14. And in a mother phrase …

15. CONT value is the same as head
daughter

16. [she walks]

17. CONT of the sentence is the same as
the CONT of the verb

18. Here’s the CONT of [walks] if it takes
[she] as a subject

19. It says some individual is a walker!

20. That individual is 3rd, sing, female

21. And that CONTENT is structure shared
with the sentence CONTENT

22. Because of a simple rule

23. Notice the features match through the
HEAD

24. Because it’s Head-driven phrase
structure grammar

25. VALENCE (SUBCAT) is the exception

26. But that’s natural

27. Let’s look at some more VALENCE

28. VALENCE = SUBCATEGORIZATION

29. [sees] takes a nominative NP subject

30. [sees] takes a CONT [3rd, sing] subject

31. Complements are in COMPS

32. [sees] doesn’t specify CONT of the
complement

33. Notice the CONT of the subject and
complement (object) …

34. … structure-shared in CONT of the
verb

35. [She saw him] is OK

36. [him saw she] is no good

37. [she saw her] – what about the CONT
of the verb?

38. Look at CONT of [she]

39. CONT of [her]

40. Here’s [sees] again

41. Look at its CONT

42. The SEER in CONT will be …?

43. The CONT of [she]

44. And the SEEN in CONT of [sees] …?

45. Matched with CONT of [her]

46. What will all this look like?

47. Like this

48. This information …

49. Is enriched to this …

50. … by unification

51. How about [he sees her]?

52. [he sees her] subject is male

53. Not much difference

54. How about [he sees us]?

55. [her] is 3rd, sing, fem

56. [us] is 1st, plural

57. Not specified for gender

58. Exciting?

59. Of course it is!!