English often contains verbs whose subjects are understood even when no noun appears next to them.
Maya tried to leave. Who leaves? Maya. Maya seemed to leave. Again, Maya is associated with leaving. Yet the relationship is not the same.
In Maya tried to leave, Maya is the person who tries and the person who is understood as the subject of leave. In Maya seemed to leave, Maya is not really the experiencer or agent of seem; the sentence is closer in meaning to It seemed that Maya left.
This difference leads into two important families of English syntax: control and raising.
For the wider architecture, begin with How English Works and the English Learning Hub. These mechanisms connect directly to Clause Embedding and Complementation, Verb Valency and Argument Structure, and Long-Distance Dependencies.
The shortest useful definition
Control constructions contain an understood subject whose reference is determined by another argument in the sentence. Raising constructions place an argument in a higher clause even though that argument receives its main semantic role from a lower clause.
The distinction sounds abstract, but it explains why superficially similar sentences behave differently.
Subject control: Maya tried to leave
In Maya tried to leave, the understood subject of leave is Maya.
The verb try requires a participant who performs the trying. Maya receives a semantic role from try. That same participant controls the understood subject of the infinitive.
- Maya tried to leave.
- Daniel promised to help.
- The children decided to wait.
In each case, the matrix subject controls the understood subject of the lower infinitive.
Object control: Maya persuaded Daniel to leave
Control can also come from an object.
Maya persuaded Daniel to leave. The person who leaves is Daniel, not Maya. The object of persuaded controls the understood subject of leave.
- Maya asked Daniel to wait.
- The teacher encouraged the class to continue.
- The rules require applicants to provide identification.
The selecting verb determines which higher argument controls the lower subject.
Why control verbs assign meaning to their controllers
A control verb usually imposes semantic requirements on its controller.
Try normally requires an entity capable of intention or effort. Promise requires a promiser. Persuade requires a persuader and someone persuaded.
This is why nonsense appears when incompatible subjects are inserted: The rock tried to apologise sounds odd unless the rock is personified. The higher verb itself places semantic demands on the subject.
Control therefore belongs closely to argument structure.
Raising: Maya seems to understand
Now compare Maya seems to understand.
The verb seem does not require Maya to perform a special “seeming” action. The sentence is closely related to It seems that Maya understands.
Maya receives its main semantic role from understand, not from seem. Syntactically, however, Maya appears as the subject of the higher clause.
This is why the construction is called raising: an argument associated semantically with the lower predicate appears in a higher grammatical position.
The expletive test
One of the clearest ways to distinguish raising from control is to test whether a non-referential subject such as there can appear.
- There seems to be a problem. — natural.
- There appears to be a problem. — natural.
- There tried to be a problem. — not an ordinary control reading.
Raising verbs can accept expletive subjects because they do not assign an ordinary semantic role to the raised subject. Control verbs typically cannot, because their subject must participate meaningfully in the higher event.
Idiom preservation as another test
Raising can preserve idiomatic interpretations that depend on the lower clause.
Suppose an idiom has a fixed subject–predicate relationship. If the subject can raise while the idiom meaning remains intact, that suggests the higher verb is not assigning a new semantic role to the subject.
Control constructions behave differently because the controller must satisfy the higher verb’s semantic requirements.
Subject-to-subject raising
Classic subject-raising verbs include seem and appear.
- The system seems to work.
- The results appear to confirm the hypothesis.
- There seems to be a delay.
The higher clause contributes evidential or appearance-related meaning while the raised subject belongs semantically with the lower predicate.
This connects naturally to modality and evidentiality because verbs such as seem and appear weaken commitment to the embedded proposition.
See Modality.
Object-to-subject-like patterns and exceptional case marking
English also has constructions such as I believe Maya to be honest or We expected the train to arrive on time.
The noun phrase before the infinitive is semantically connected to the lower predicate: Maya is honest; the train arrives. Yet it occupies a position licensed by the higher construction.
Different grammatical theories analyse the details differently, but the practical insight is stable: English can link an argument across clause boundaries without repeating a full finite clause.
Control with promise and persuade
Some verbs are useful because they show that surface proximity does not determine control.
Maya promised Daniel to leave. Under the ordinary interpretation, Maya is understood as the one who leaves. Even though Daniel sits closer to the infinitive, promise is a subject-control verb.
Maya persuaded Daniel to leave. Here Daniel leaves. Persuade is object control.
This contrast shows why learners cannot solve control by choosing the nearest noun. The selecting verb determines the dependency.
Implicit subjects and PRO
Many formal syntactic theories represent the understood subject of a control infinitive with a silent element often written as PRO.
In Maya tried [PRO to leave], PRO is understood as Maya. The notation helps linguists distinguish a genuinely unpronounced subject from a simple absence of structure.
Students do not need the label to use English correctly, but the idea is valuable: some unspoken meanings are structurally represented rather than merely guessed from context.
Control and purpose clauses
Purpose infinitives often have an understood subject linked to the main clause.
Maya went to the library to study. Maya is understood as the person who studies. The teacher gave Maya a book to read. Depending on structure and context, Maya can be understood as the reader.
These constructions reveal how English compresses chains of intention into one sentence without restating every participant.
Raising changes information packaging
Compare It seems that the system is unstable with The system seems to be unstable.
The propositional content is close, but the second version places the system in subject position. That can improve discourse continuity when the system is already the topic.
Raising therefore interacts with information structure. Syntax can move a semantically lower argument upward to preserve the current discourse thread.
See Topic and Focus.
Why seem and try are not interchangeable
The child tried to sleep describes an effort by the child. The child seemed to sleep describes the speaker’s assessment of appearances.
The first construction introduces an intentional event in the higher clause. The second introduces an evidential frame around the lower proposition.
This difference affects entailment. If Maya tried to leave, it does not follow that she left. If Maya seemed to leave, the sentence does not assert with certainty that she left either, but for a different reason: the speaker weakens commitment through appearance or evidence.
Control and responsibility
Control constructions often encode intention, obligation or influence.
- She decided to resign. — intentional control.
- They forced him to resign. — external causation.
- They allowed him to resign. — permission.
- They expected him to resign. — expectation, not necessarily control in the same syntactic sense.
The choice of higher verb therefore changes the participant network around the lower action.
Control and ambiguity
Some infinitival structures become ambiguous when more than one participant could plausibly control the understood subject.
Maya discussed the report with Daniel before leaving. Who left? Maya is often preferred because she is the main-clause subject, but context can influence interpretation.
Writers should make the controller explicit when ambiguity would matter: Before Maya left, she discussed the report with Daniel.
Control in instructions and policy language
Formal documents frequently use control verbs to assign obligations and permitted actions.
Applicants are required to submit identification. Participants are encouraged to arrive early. Users are advised to retain a copy.
The understood subject of the infinitive is controlled by the participant identified in the higher clause. These constructions compress institutional instruction into a standard template.
Raising in academic writing
Academic prose often uses raising predicates to calibrate certainty.
- The evidence appears to support the hypothesis.
- The effect seems to be temporary.
- The results are likely to change.
These structures allow the proposition to remain the grammatical topic while the writer places an evidential or modal frame around it.
A compact diagnostic table
| Construction | Higher subject/object gets semantic role from higher verb? | Who is understood as lower subject? |
|---|---|---|
| subject control | yes | higher subject |
| object control | yes | higher object |
| subject raising | not in the ordinary thematic sense | raised subject belongs semantically to lower predicate |
| exceptional infinitive | construction-dependent | noun before infinitive |
A practical method for students
- Find the infinitive. Which clause has an unspoken subject?
- Ask who performs the lower action. Which participant is understood?
- Inspect the higher verb. Does it assign a semantic role to that participant?
- Try an expletive. Can there appear naturally? If so, raising is likely.
- Paraphrase with a finite clause. Does It seems that… preserve the meaning?
- Check ambiguity. If more than one controller is plausible, rewrite.
Why control and raising belong inside How English Works
Control and raising reveal that English can distribute one participant across several layers of clause structure without repeating it.
In control, a participant belongs meaningfully to the higher verb and also determines the silent subject below. In raising, a participant associated semantically with the lower predicate appears in a higher grammatical position so the sentence can carry evidential, modal or discourse information around it.
Once this distinction is visible, sentences such as Maya tried to leave and Maya seemed to leave stop looking structurally identical. One is about effort. The other is about how a proposition appears.
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