1. xin li xue   botany   history   psychology   algebra   Hint Half-n-half Clue   2. tian wen   geometry   philosophy   astronomy   geology   Half-n-half Clue   3. [ji;ji] [he;he]   biology   astronomy   geometry   history   Half-n-half Clue   4. san [jia;jiao;jue] xue   geology   psychology   trigonometry   geometry   Half-n-half Clue   5. dong wu xue   calculus   geology   zoology   chemistry   Half-n-half Clue   6. zhe xue   calculus   philosophy   history   geology   Half-n-half Clue   7. zhi wu xue   biology   botany   geology   algebra   Half-n-half Clue