Topic Marker は and Subject Marker が

To study this grammar point, please make sure you understand the following:

A topic particle (or topic marker) (pronounced as /wa/) essentially introduces the topic of a sentence. The listener will expect you to continue to say more about the topic when you use the topic marker.

You can also consider the topic marker は equivalent to as for in English.

On the contrary, a subject marker indicates that the speaker wants to identify something new into the conversation.

The name topic marker and subject marker are misleading, because the markers may or may not be marking the subject of the sentence.

It is often confusing for beginning learners to decide whether topic or subject marker should be used. You need to learn by reading more examples and understanding them case by case.

John is a student.
As for John, he is a student. (There may be other students among the people we’re talking about.)

Both topic marker and subject marker can be used in the same sentence.

It is John who is the student.
John is the student among all the people we are talking about.

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