| disturbing(adjective, hard, difficult, complex) |
| operose(adjective, hard, difficult, complex) |
| sad(adjective, hard, difficult, complex) |
| cruel(adjective, hard, difficult, complex) |
| dire(adjective, hard, difficult, complex) |
| unbearable(adjective, hard, difficult, complex) |
| exacting(adjective, hard, tough, severe, rough) |
| onerous(adjective, hard, difficult, harsh, heavy) |
| strenuous(adjective, difficult) |
| troublesome(adjective, hard, tough, severe, difficult) |
| exigent(adjective, hard, difficult, harsh, heavy) |
| tiring(adjective, hard, severe, difficult, harsh) |
| charging(verb, pricing) |
| exhausting(adjective, hard, severe, difficult, heavy) |
| fatiguing(adjective, hard, tough, severe, difficult) |
| burdening |
| draining(verb, adjective, difficult, demanding, strenuous) |
| heavy(adjective, heavy) |
| rating(noun, verb, pricing) |
| straining |