1. 问题   homework   question   read   lesson   Hint Half-n-half Clue   2. 更正   lesson   read   answer   correction   Half-n-half Clue   3. 教   homework   teach   read   correction   Half-n-half Clue   4. 教学   teach   mark   teaching   answer   Half-n-half Clue   5. 家庭作业   homework   mark   study   teach   Half-n-half Clue   6. 教训   study   lesson   learn   homework   Half-n-half Clue   7. 学会   study   learn   homework   lesson   Half-n-half Clue