Theme / What We Say Something About
What is the statement about?
意味
The participant or idea that the sentence is mainly about, even if it is not actively doing anything.
見分け方
Ask what the sentence is making a statement about.
例
the book|this problem|my brother|it
as for the book|this problem is difficult
This book is expensive.
Visual guide
ABOUT frame:
[This book]
↓ comment about it
[is expensive]
Topic/theme = what
statement is about
Same idea, two shapes: [This book] [is expensive] subject/topic comment [As for the book], [expensive] topic frame + comment
言語別ビュー
母語の仕組み
Japanese strongly separates topic with は from subject-like marking with が.
この本は高い。
As for this book, expensive.
学習言語では
English has topic-comment patterns, but ordinary subject-verb-object order is more common than strong topic marking.
This book, I really enjoyed.
this book = the topic
Learners may copy topic-heavy structures from their native language and produce unnatural English word order.
Same block, different coding
Both languages use this block strongly, but they signal it differently. Focus on form changes, not only meaning.