A (深) 深 shen1 
deep/ difficult/ thoroughgoing/ dark 
1. tief 2. schwer, schwierig, tief 3. tiefschürfend, eingehend 4. eng, intim, tief 5. tief, dunkel 6. spät 7. sehr, tief B (艱巨) 艰巨 jian1ju4
arduous/ hard/ formidable
schwer, schwierig mühsam C (艱難) 艰难 jian1nan2
hard/ difficult/ arduous
schwer, schwierig D (繁重) 繁重 fan2zhong4
heavy/ onerous
schwer, schwierig
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繁 繁 complicated, complex, difficult
重 重 heavy, weighty / double
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C (艱難) 艰难 jian1nan2 hard/ difficult/ arduous schwer, schwierig