Draw a shorter vertical line to the right of the verb. This line should not cross through the baseline; it simply sits on top of it.
Write the subject on the left side of the vertical line and the verb on the right. Sentence Diagramming Step-by-Step Guide
Every diagram begins with the "skeleton"—the simple subject and the main verb. Start by drawing a long horizontal line. Draw a shorter vertical line to the right of the verb
Draw a vertical line that cuts completely through the horizontal baseline. Sentence Diagramming Step-by-Step Guide
Modifiers like "the," "red," or "quickly" describe the main parts of the sentence. A Step-by-Step Guide to Diagramming Sentences (Video)

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