| laborious(adjective, hard, great, tough, difficulty) |
| arduous(adjective, hard, great, tough, difficulty) |
| hard(adjective, great, tough, difficulty, difficult) |
| difficult(adjective, hard, great, tough, difficulty) |
| tough(adjective, hard, difficulty, difficult, complex) |
| burdensome(adjective, hard, tough, difficult, complex) |
| backbreaking(adjective, hard, difficult, complex, awkward) |
| operose(adjective, hard, tough, difficulty, difficult) |
| rough(adjective, hard, great, tough, difficult) |
| severe(adjective, hard, tough, difficult, harsh) |
| trying(adjective, hard, difficult, complex, weary) |
| knotty(adjective, hard, difficult, complex, awkward) |
| complex(adjective, hard, difficult) |
| painful(adjective, hard, difficult, complex) |
| punishing(adjective, hard, difficult, complex) |
| stressful(adjective, hard, difficult, complex) |
| tricky(adjective, hard, difficult, complex, awkward) |
| rugged(adjective, hard, difficult, harsh, cruel) |
| complicated(adjective, hard, difficult, complex, awkward) |
| grinding(adjective, hard, difficult, harsh, cruel) |