What the sentence is about
Who or what are we saying something about?
Significado
A sentence can tell us what someone or something does, what it is like, or what happens to it. That person or thing is the center of the statement, even when it does not act. Languages may use word order or verb forms to link it to the statement, and some need no separate word when it is understood. Topic is the chosen starting point for a message and can be a different participant.
Como identificar
Ask which person or thing is presented as doing something, being something, or having something happen to it, not just which one is mentioned first.
Na tua língua materna
The subject normally comes before the verb, but it can also follow it or remain unspoken when understood. In standard Portuguese, the verb agrees with the subject, changing to match who is involved and whether it is singular or plural. The subject may be a doer, someone in a state, or something affected by an event; it is not necessarily the topic, the chosen starting point of the message.
As crianças estão com sono.
The plural verb matches the plural subject, which is not a doer.
A porta ficou aberta a noite toda.
Chegaram duas encomendas hoje.
The subject follows the verb, which still takes the plural form.
Na tua língua de aprendizagem
English usually uses the subject to name the person or thing it makes a statement about. In an ordinary statement, the subject comes before the verb and can name a doer, someone in a state, or something affected by an action. It is not always the topic or the first phrase in the sentence.
Ella is tired.
Ella is the subject, but she is not carrying out an action.
My bag was found at the station.
The passive sentence presents the bag as the subject, not the person who found it.
After lunch, the kitchen was quiet.
The opening phrase gives the time; the kitchen is the subject.
Learners whose language freely moves sentence parts may move an object into the subject's place and change the meaning. Learners whose language leaves known subjects unspoken may omit a subject that English requires.