以下のコードを試してみてください。
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<p>Pennsylvania State Standards, Subject 1: Reading, Writing, Speaking, and Listening</p>
<ul>
<li><input type="checkbox" rel="textbox" name="1.1. Reading Independently">1.1. Reading Independently</input></li>
<li><input type="checkbox" rel="textbox" name="1.2. Reading, Analyzing, and Interpreting Text">1.2. Reading, Analyzing, and Interpreting Text</input></li>
<li><input type="checkbox" rel="textbox" name="1.3. Reading, Analyzing, and Interpreting Literature: Fiction and Non-Fiction">1.3. Reading, Analyzing, and Interpreting Literature: Fiction and Non-Fiction</input></li>
<li><input type="checkbox" rel="textbox" name="1.4. Types of Writing">1.4. Types of Writing</input></li>
<li><input type="checkbox" rel="textbox" name="1.5. Quality of Writing">1.5. Quality of Writing</input></li>
<li><input type="checkbox" rel="textbox" name="1.6. Speaking and Listening">1.6. Speaking and Listening</input></li>
<li><input type="checkbox" rel="textbox" name="1.7. Characteristics and Functions of the English Language">1.7. Characteristics and Functions of the English Language</input></li>
<li><input type="checkbox" rel="textbox" name="1.8. Research">1.8. Research</input></li>
<li><input type="checkbox" rel="textbox" name="1.9. Information, Communication, and Technology Literacy">1.9. Information, Communication, and Technology Literacy</input></li>
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