1. Three kinds of empty arguments
Pro-drop: The empty argument is understood with a definite reference: he, she, it, they, etc.
Optional argument with indefinite reference.
Semantic valency change.

2. Pro-drop English sentences almost always have a subject noun phrase:
She studied.
Dummy or pleonastic subjects:
It is raining
There is a problem.
Apparent exceptions due to ellipsis:
Does he like chocolate? Seems to.
What are you going to do? Study real hard.

3. Pro-drop languages
The subject noun phrase can be missing, but is understood as a pronoun referring to something specific:
Your language here.
The direct object noun phrase (or other noun phrases) can also be dropped in some languages.

4. Optional arguments in English
The children ate chocolate.
The children ate.
What does this mean?
What happened to the cake?
The children ate it.
*The children ate.

5. Optional argument vs. semantic valency change
The pirates sank the boat.
The boat was sunk by the pirates.
The boat was sunk.
The boat sank.
The boat was sunk to destroy the enemy.
Presence of a purpose clause indicates that there is an unspecified agent. Two semantic roles: agent and theme.
*The boat sank to destroy the enemy.
Inability to take a purpose clause indicates that the sentence contains only one semantic role – theme.

6. Behavioral Properties of Subjects (1): Imperatives
An imperative is a command.
Close the door.
Addressed to an agent who can carry out the command.
It’s hard to make an imperative with non-agentive verbs:
? Be tall.
? Know the answer by the time I get back.

7. Imperatives
We know that the addessee of an imperative has to be an agent, but does it have to be a subject?
Sentences such as passives have agents that are not subjects.
English:
*The clothes be washed.
Not an imperative
Let the clothes be washed!
Addressee is the subject of let, not the agent of wash
The cost be damned!
A special exclamation. Not really an imperative. Addressee doesn’t do the damning.

8. Imperatives Malagasy (Madagascar): (Van Valin 2.39b) Sasao ny lamba.
wash.passive the clothes
The clothes be washed! (imperative)

9. Behavioral Properties of Subjects (2): Reflexives (and notation for pronoun reference)
Antecedent: What a pronoun refers to.
Who is John(i)? He(i) is my brother.
John(i) thought that he(i/j) would go.
John can be the antecedent of he in both examples.
Reflexive Pronoun:
I(i) saw myself(i/*j).
You saw yourself.
He saw himself.
Etc.

10. Reflexive Pronouns in English
James(i) saw himself(i).
Antecedent is subject.
James(i) told Miriam(j) about himself(i).
James(i) told Miriam(j) about herself(j).
Antecedent is direct object.
Miriam(j) talked to/with Sam(i) about himself(i).
Antecedent is oblique (prepositional phrase).

11. Reflexive Pronouns in Norwegian
Jon(i) fortalte meg om seg selv(i).
John told me about himself.
(Antecedent is subject.)
*Vi fortalte Jon(i) om seg selv(i).
We told John about himself.
Antecedent must be the subject.

12. Reflexive Pronouns in Norwegian
*Jon(i) snakker om ham selv(i).
John talks about himself.
(Antecedent is subject.)
Vi fortalte Jon(i) om ham selv(i).
We told John about himself.
Antecedent cannot be the subject.