diff --git a/lesson-1B.module b/lesson-1B.module
index c97801a..da8042d 100644
--- a/lesson-1B.module
+++ b/lesson-1B.module
@@ -9,22 +9,53 @@ VOICE_DEFAULT: aoede | Clear, friendly American English narrator
 $LESSON Lesson 1B
 
 # --- Figure 1 -------------------------------------------------------------
-# The tape provides groups of past-tense verbs by their -ed ending sound,
-# followed by a repetition drill. We map this to $DIALOGUE REPEAT.
-$DIALOGUE Figure 1: Pronunciation of -ed Endings
-INTRO: You will hear past tense verbs grouped by how their E D endings sound. Listen to the groups, and then repeat the words.
-INSTRUCTION: Repeat the words.
+# The book groups past-tense verbs into three columns by the sound of the -ED
+# ending (/d/, /t/, /id/); the tape reads each column word by word with repeat
+# pauses. One $DIALOGUE REPEAT per column, ONE LINE PER WORD, so the learner
+# repeats each word at their own pace. (Word timings via forced alignment.)
+$DIALOGUE Figure 1: -ED Endings — the D Sound
+INTRO: Mary lived in Spain last year. "Lived" ends with a D sound. Listen and repeat these past tense verbs.
+INSTRUCTION: Repeat each word.
 REPEAT
 
-LINE: Answered. {bk04-l1b-f1-01.mp3}
-LINE: Circled. {bk04-l1b-f1-02.mp3}
-LINE: Cleaned. {bk04-l1b-f1-03.mp3}
-LINE: Closed. {bk04-l1b-f1-04.mp3}
-LINE: Listened, lived, memorized, opened, played, reviewed, shaved, spelled, studied. {bk04-l1b-f1-05.mp3}
+LINE: answered {bk04-l1b-f1-01.mp3}
+LINE: circled {bk04-l1b-f1-02.mp3}
+LINE: cleaned {bk04-l1b-f1-03.mp3}
+LINE: closed {bk04-l1b-f1-04.mp3}
+LINE: learned {bk04-l1b-f1-05.mp3}
+LINE: listened {bk04-l1b-f1-06.mp3}
+LINE: lived {bk04-l1b-f1-07.mp3}
+LINE: memorized {bk04-l1b-f1-08.mp3}
+LINE: opened {bk04-l1b-f1-09.mp3}
+LINE: played {bk04-l1b-f1-10.mp3}
+LINE: reviewed {bk04-l1b-f1-11.mp3}
+LINE: shaved {bk04-l1b-f1-12.mp3}
+LINE: spelled {bk04-l1b-f1-13.mp3}
+LINE: studied {bk04-l1b-f1-14.mp3}
 
-LINE: Talked, cooked, liked, looked, looked up, marked, walked, watched, worked. {bk04-l1b-f1-06.mp3}
+$DIALOGUE Figure 1: -ED Endings — the T Sound
+INTRO: Mark talked to his friends. "Talked" ends with a T sound. Listen and repeat.
+INSTRUCTION: Repeat each word.
+REPEAT
 
-LINE: Started, visited, wanted. {bk04-l1b-f1-07.mp3}
+LINE: cooked {bk04-l1b-f1-15.mp3}
+LINE: liked {bk04-l1b-f1-16.mp3}
+LINE: looked {bk04-l1b-f1-17.mp3}
+LINE: looked up {bk04-l1b-f1-18.mp3}
+LINE: marked {bk04-l1b-f1-19.mp3}
+LINE: talked {bk04-l1b-f1-20.mp3}
+LINE: walked {bk04-l1b-f1-21.mp3}
+LINE: watched {bk04-l1b-f1-22.mp3}
+LINE: worked {bk04-l1b-f1-23.mp3}
+
+$DIALOGUE Figure 1: -ED Endings — the ID Sound
+INTRO: The show started at eight. "Started" ends with an ID sound. Listen and repeat.
+INSTRUCTION: Repeat each word.
+REPEAT
+
+LINE: started {bk04-l1b-f1-24.mp3}
+LINE: visited {bk04-l1b-f1-25.mp3}
+LINE: wanted {bk04-l1b-f1-26.mp3}
 
 # --- Figure 2 -------------------------------------------------------------
 # Written verb transformation (cloze) mapped to $PRODUCE with type/exact.
@@ -36,17 +67,20 @@ INPUT: type
 CHECK: exact
 
 TEMPLATE: Danny ____ his friends in Dallas last year. (visit)
-RESPONSE: visited {bk04-l1b-f2-01.mp3}
+RESPONSE: Danny visited his friends in Dallas last year. {bk04-l1b-f2-01.mp3}
+ACCEPT: visited
 
 TEMPLATE: George ____ to go to the movies yesterday. (want)
-RESPONSE: wanted {bk04-l1b-f2-02.mp3}
+RESPONSE: George wanted to go to the movies yesterday. {bk04-l1b-f2-02.mp3}
+ACCEPT: wanted
 
 TEMPLATE: The show ____ at 8:00 and it ____ at 10:00 last night. (start) (end)
-RESPONSE: started, ended {bk04-l1b-f2-03.mp3}
-ACCEPT: started ended | started and ended
+RESPONSE: The show started at 8:00 and it ended at 10:00 last night. {bk04-l1b-f2-03.mp3}
+ACCEPT: started, ended | started ended | started and ended
 
 TEMPLATE: The teacher ____ the tests this morning. (correct)
-RESPONSE: corrected {bk04-l1b-f2-04.mp3}
+RESPONSE: The teacher corrected the tests this morning. {bk04-l1b-f2-04.mp3}
+ACCEPT: corrected
 
 # --- Figure 3 -------------------------------------------------------------
 # Written verb transformation (cloze) mapped to $PRODUCE with type/exact.
@@ -57,19 +91,24 @@ INPUT: type
 CHECK: exact
 
 TEMPLATE: Jane ____ the new words in the dictionary. (look up)
-RESPONSE: looked up {bk04-l1b-f3-01.mp3}
+RESPONSE: Jane looked up the new words in the dictionary. {bk04-l1b-f3-01.mp3}
+ACCEPT: looked up
 
 TEMPLATE: Bob ____ to his friends yesterday. (talk)
-RESPONSE: talked {bk04-l1b-f3-02.mp3}
+RESPONSE: Bob talked to his friends yesterday. {bk04-l1b-f3-02.mp3}
+ACCEPT: talked
 
 TEMPLATE: The students ____ questions last week. (ask)
-RESPONSE: asked {bk04-l1b-f3-03.mp3}
+RESPONSE: The students asked questions last week. {bk04-l1b-f3-03.mp3}
+ACCEPT: asked
 
 TEMPLATE: We ____ the basketball game last night. (like)
-RESPONSE: liked {bk04-l1b-f3-04.mp3}
+RESPONSE: We liked the basketball game last night. {bk04-l1b-f3-04.mp3}
+ACCEPT: liked
 
 TEMPLATE: Mrs. Franklin ____ all week long in the office. (work)
-RESPONSE: worked {bk04-l1b-f3-05.mp3}
+RESPONSE: Mrs. Franklin worked all week long in the office. {bk04-l1b-f3-05.mp3}
+ACCEPT: worked
 
 # --- Figure 4 -------------------------------------------------------------
 # Written verb transformation (cloze) mapped to $PRODUCE with type/exact.
@@ -81,19 +120,24 @@ INPUT: type
 CHECK: exact
 
 TEMPLATE: Peter ____ up his room last weekend. (clean)
-RESPONSE: cleaned
+RESPONSE: Peter cleaned up his room last weekend.
+ACCEPT: cleaned
 
 TEMPLATE: Danny ____ the window this morning. (open)
-RESPONSE: opened
+RESPONSE: Danny opened the window this morning.
+ACCEPT: opened
 
 TEMPLATE: Claire ____ French last year. (study)
-RESPONSE: studied
+RESPONSE: Claire studied French last year.
+ACCEPT: studied
 
 TEMPLATE: Mr. and Mrs. Adams ____ in Houston 5 years ago. (live)
-RESPONSE: lived {bk04-l1b-f4-01.mp3}
+RESPONSE: Mr. and Mrs. Adams lived in Houston 5 years ago. {bk04-l1b-f4-01.mp3}
+ACCEPT: lived
 
 TEMPLATE: The airmen ____ two games last week. (play)
-RESPONSE: played {bk04-l1b-f4-02.mp3}
+RESPONSE: The airmen played two games last week. {bk04-l1b-f4-02.mp3}
+ACCEPT: played
 
 # --- Figure 5 -------------------------------------------------------------
 # Sound discrimination S/D mapped to $SELECT. Shared options pool.
@@ -185,6 +229,10 @@ INSTRUCTION: Tap the sound you hear in the word.
 OPTION: a | AH sound (as in cop)
 OPTION: b | UH sound (as in cup)
 
+EXAMPLE
+PROMPT: pot {bk04-l1b-f7-00.mp3}
+ANSWER: a
+
 PROMPT: job {bk04-l1b-f7-01.mp3}
 ANSWER: a
 
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