Embedded Clauses in TAG Embedded Clauses Matrix Clause

Embedded Clauses in TAG

Embedded Clauses Matrix Clause S NP VP V S-bar Embedded Clause S COMP We think that NP VP they have left.

Linguistic Background • Constraints • Semantic roles

Embedded Clauses: Constraints • Main verbs are subcategorized for – The complementizer (that, for, to, etc. ) Nonfinite for-to – We hoped for there to be no trouble. • A word at the beginning of a subordinate clause that identifies it as a complement – The morphology of the embedded verb • Finite: present or past tense • Non-finite: infinitive, present participle, past participle

Examples: Constraints imposed by the main verb on the embedded verb • “Say” requires a finite embedded clause: – Sam said that Sue saw him. – *Sam said Sue to see him. – *Sam said that Sue seeing him. • “that” is a complementizer that goes with finite clauses. When it comes after a verb, it is optional: – Sam said Sue saw him. – That he left is a problem. – *He left is a problem. • “That” is only optional after a verb.

Examples: Constraints imposed by the main verb on the embedded verb • “Expect” takes a finite clause or an infinitive, but not a participle: – We expect to see him. – We expect that we will see him. • Modal auxiliary verbs (will, would, may, might, can, could, shall, should, etc) are always finite. – *We expect seeing him. • Might sound grammatical because “seeing him” can be a noun phrase, and “expect” can occur with a noun phrase: “We expect problems” – *We expect seen him.

Finite embedded clauses • Finite embedded clause – I believe (that) it is snowing. – Say, think, scream • Finite with dummy subject – It seems that they have left. • Finite embedded question – I wondered/asked whether/if it was snowing. • Finite plus object – We told them that it was snowing. • Finite plus PP – We said to them that it was snowing.

Non-finite embedded clauses • Non-finite for-to – We hoped for there to be no trouble. • Non-finite: Raising to subject – They seem (to us) to have left. – Appear, continue • Non-finite: Subject Equi – They tried to leave. – Intend, expect, plan, hope • Non-finite: Raising to object – We believe them to have left. – consider • Non-finite: Object Equi – We persuaded them to leave. – Convince, order, force, signaled • Non-finite: promise – We promised them to leave.

English Auxiliary Verbs • Modal verbs: (will, would, can, could, shall, should, may, might, and a few others) – Invariant: don’t have a third person singular form. – Only occur where you can have present or past tense. Don’t occur in infinitives, gerunds, or participles: • • I will go. I would go. I said I would go. *I want to can go. – Compare: I want to be able to go. • *Canning go would make me happy. – Compare: Being able to go would make me happy. – The next verb must be an infinitive without “to”. • I will have gone. • I will be going. • *I will going/gone/went/goes.

English Auxiliary Verbs • “Have” – Must be followed by a past participle: • I have gone. • *I have going/went/goes/go. • Progressive “be” – Must be followed by a present participle: • I am going. • *I am goes/went/go. • Passive “be” – Must be followed by a passive verb: • The cookies were devoured. • *The cookies were devouring/devours/devour.

Auxiliary verbs as main verbs (for syntax; not for semantics) • The auxiliary verb can impose constraints on the main verb. – Sam is sleeping/*slept/*sleeps. • The main clause has to be finite (has a tense). – Sam sleeps/slept. – *Sam to sleep. – *Sam sleeping. • The auxiliary verb carries the tense, not the main verb: – Sam is sleeping. – *Sam be sleeps.

S NP VP V Sam VP is sleeping S NP Sam VP V VP has slept

Summary of constraints on embedded clauses • The main verb determines the tense and morphology of the embedded verb. • More than one embedded clause: – Each verb determines the tense and morphology of the next one: • I think that Sam tried to sleep. • “Think” requires “try” to be finite. • “Try” requires “sleep” to be infinitive.

The car needs washed. • In most dialects of English, “need” takes an infinitive as a complement: – The car needs to be washed. – Sam needs to sleep. • There a few verbs that take passive participles as complements: – – We had them arrested by the police. We got them arrested by the police. They were arrested by the police. They got arrested by the police. • In Pittsburgh, “need” and “want” can take passive participles as complements: – The car needs washed. – Do you want pushed?

Semantic Roles • Syntax – Word order – Constituent structure – Constraints: agreement, subcategorization, case marking – Semantic roles: • Sue interviewed Sam. • Sue is the interviewer. • Sam is the interviewee.

Semantic Roles in Embedded Clauses • Sam tried to sleep. – Sam is the agent of “try” – Sam is the agent of “sleep” – “Sam to sleep” is what was tried. • Sam seemed to sleep. – Sam is the agent of “sleep. ” – Sam is not an argument of “seem. ” – “Sam to sleep” is the only argument of “seem”.

Just the facts • How many semantic arguments does each verb take: – “Try” takes two. – “Seem” takes one. • Do the main clause and the embedded clause share a subject? – Yes. Both “seem” and “try” share their subjects with the embedded verb.

How we know that the semantic role assignments are different with Seem and Try • The cat seems to be out of the bag. • There seems to be a problem. • That seems to be my husband. • The doctor seemed to examine Sam. • Sam seemed to be examined by the doctor. • The cat tried to be out of the bag. • *There tried to be a problem. • That tried to be my husband. • The doctor tried to examine Sam. • Sam tried to be examined by the doctor.

Raising to subject S NP S VP V NP S-bar VP V VP-bar S COMP It seems that NP VP VP COMP they have left. They seem to have left.

S NP VP V VP-bar Two ways to represent that “seem” and “leave” share a subject. VP COMP They seem to have left. S NP VP V S NP They seem e VP to have left. Subj Verb Complement they seem subj verb leave

Comparison • Second method: – Allow empty strings as terminal nodes in the tree. – An empty string needs to take the place of the missing subject of the lower clause. – The empty string is linked to the subject of the main clause to show that the main and embedded clauses share a subject. – The tree represents: word order, constituent structure, grammatical relations, semantic roles. • First method: – No empty strings in the tree. – The tree represents only word order and constituent structure. – Grammatical relations and semantic roles are represented in a separate structure. – Structure sharing in the representation of grammatical relations shows that the two verbs share a subject. • Is one method simpler than the other? – No. Both methods have to represent word order, semantic relations, grammatical relations, and semantic roles. • People who argue that one is simpler are usually wrong – they don’t know how to count steps in a derivation.

Two ways to represent that “try” and “leave” share a subject. S NP VP V VP-bar Subj Verb Complement VP COMP They try to they seem subj verb leave. S NP PRO is an empty string, but not the same kind of empty string as e VP V S NP They(i) try VP Coindexing indicates that PRO refers to “they”. PRO(i) to leave.

“Seem” type verbs in TAG VP S NP VP V John Adjunction site AP to be happy Initial Tree V VP seem Auxiliary Tree These trees represent the number of arguments for each verb: “Seem” has one argument, represented as a VP. “To be happy” has one argument, “John”.

S NP VP V AP to be happy John VP Adjunction site V seem VP

S NP V VP VP V VP seems V Adjunction VP seem AP to be happy VP V John VP AP to be happy John This tree shows word order and constituent structure. It also shows that “John” is the subject of “seem. ” It doesn’t show that “John” is the subject of “to be happy. ”

“Try” type verbs in TAG S S NP NP VP V John VP TO S PRO tried Auxiliary Tree Adjunction site VP leave Initial Tree These trees show the number of arguments for each verb: “Try” has two arguments. “Leave” has one argument.

S NP VP V John tried S S NP Adjunction site VP TO PRO VP leave

Adjunction is only allowed at the top S node so as not to mess up compositional semantics: After you put together “try to leave” you don’t want to have to take it apart again by inserting another verb like “expected” as in: John tried to expect to leave. Inserting “seem” into the middle of the tree doesn’t require you to disassemble any of the semantic pieces that were already assembled? S NP VP V John S tried. NP VP TO PRO VP leave