book 7 session 1-2: rubric guides the two category items ('They're called shapes')

Those items show a group of different shapes and want the CATEGORY word, so a
learner naming the individual shapes — perfectly good English — was marked wrong
with no idea why (Elena). The grader is now told to say so and hint that one word
covers them all.

Co-authored-by: Cursor <cursoragent@cursor.com>

book-7-lesson-1.module

@@ -234,7 +234,7 @@ INTRO: Time to name the shapes yourself. Look at each picture and say what it's
 INSTRUCTION: Look at the picture and say what the shape is called.
 INPUT: speak
 CHECK: llm
-RUBRIC: Treat the model answer as the key; accept any phrasing that names the same shape (e.g., "a triangle" or "It's called a triangle.").
+RUBRIC: Treat the model answer as the key; accept any phrasing that names the same shape (e.g., "a triangle" or "It's called a triangle."). Two items ask about a group and want the CATEGORY word ("They're called lines." / "They're called shapes."): if the learner instead lists the individual shapes ("a triangle, a square"), that is not the target — say so and hint that one word covers all of them.
 
 EXAMPLE
 PROMPT: What's this shape called? {st-page_014_005.jpg}