関連ワード:  is grade 12 difficult    is grade 12 harder than 11    is grade 12 harder than university    is grade 12 harder    is grade 12 maths difficult    is grade 12 chemistry difficult    is grade 12 math harder than 11th    is grade 12 biology harder than 11th    is grade 12 the hardest year    is grade 12 chemistry harder than physics