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diff --git a/book-12-lesson-1.module b/book-12-lesson-1.module
index 6d6f2c41..d8419671 100644
--- a/book-12-lesson-1.module
+++ b/book-12-lesson-1.module
@@ -1632,7 +1632,7 @@ ANSWER: a
 # Source: ST §The Word May Be, Is Not, Is
 $PRODUCE May Be, Is Not, or Is?
 ID: l1-s18
-INTRO: Word detective work: each new clue tells you whether a guess about the underlined word "may be" true, "is" true, or "is not" true. Type "may be", "is", or "is not" in each blank.
+INTRO: Word detective work: pretend you don't know the underlined word. Each new clue tells you whether a guess "may be" true, "is" true, or "is not" true — judged by the sentence's clues alone, not what you already know. Type "may be", "is", or "is not" in each blank.
 INSTRUCTION: Type "may be", "is not", or "is" based on the clues in the sentence.
 INPUT: type
 CHECK: exact
diff --git a/book-12-lesson-2.module b/book-12-lesson-2.module
index d2e24c5e..3e2f50c1 100644
--- a/book-12-lesson-2.module
+++ b/book-12-lesson-2.module
@@ -962,7 +962,6 @@ TEMPLATE: yes, already
 PROMPT: Have you finished your homework yet? {bk12-l2c-f2-ex-q.mp3}
 RESPONSE: Yes, I've already finished it. {bk12-l2c-f2-ex-a1.mp3}
 ACCEPT: Yes, I have already finished it.
-ACCEPT: Yes, I have already finished it.
 
 EXAMPLE
 TEMPLATE: no, yet
@@ -986,7 +985,6 @@ TEMPLATE: yes, already
 PROMPT: Have you seen Mike's daughter yet? {bk12-l2c-f2-02-q.mp3}
 RESPONSE: Yes, I've already seen her. {bk12-l2c-f2-02-a1.mp3}
 ACCEPT: Yes, I have already seen her.
-ACCEPT: Yes, I have already seen her.
 
 TEMPLATE: no, yet
 PROMPT: Have you seen Mike's daughter yet? {bk12-l2c-f2-02-q.mp3}
@@ -998,7 +996,6 @@ TEMPLATE: yes, already
 PROMPT: Has your son learned Spanish yet? {bk12-l2c-f2-03-q.mp3}
 RESPONSE: Yes, he's already learned Spanish. {bk12-l2c-f2-03-a1.mp3}
 ACCEPT: Yes, he has already learned Spanish.
-ACCEPT: Yes, he has already learned Spanish.
 
 TEMPLATE: no, yet
 PROMPT: Has your son learned Spanish yet? {bk12-l2c-f2-03-q.mp3}
@@ -1021,7 +1018,6 @@ TEMPLATE: yes, already
 PROMPT: Has Henry picked up the laundry yet? {bk12-l2c-f2-05-q.mp3}
 RESPONSE: Yes, he's already picked it up. {bk12-l2c-f2-05-a1.mp3}
 ACCEPT: Yes, he has already picked it up.
-ACCEPT: Yes, he has already picked it up.
 
 TEMPLATE: no, yet
 PROMPT: Has Henry picked up the laundry yet? {bk12-l2c-f2-05-q.mp3}