| laborious(adjective, hard, easy, difficult, important) |
| sedate(adjective, calm, dull, cool, severe) |
| painful(adjective, bad, hard, difficult, offensive) |
| staid(adjective, calm, dull, set, cool) |
| dire(adjective, hard, difficult, complex) |
| heavyweight(adjective, hard, difficult, important, complex) |
| operose(adjective, hard, difficult, important, complex) |
| precarious(adjective, hard, difficult, complex, dangerous) |
| grim(adjective, dull, strong, hard, tough) |
| heartrending(adjective, hard, difficult, complex) |
| involved(adjective, hard, difficult, complex, awkward) |
| massive(adjective, hard, difficult, complex) |
| oppressive(adjective, hard, difficult, complex) |
| sore(adjective, hard, difficult, complex) |
| stubborn(adjective, strong, hard, tough, firm) |
| troubled(adjective, hard, difficult, unhappy, gloomy) |
| backbreaking(adjective, hard, difficult, complex, awkward) |
| burdensome(adjective, hard, difficult, big, heavy) |
| complicated(adjective, hard, difficult, complex, awkward) |
| cruel(adjective, strong, hard, tough, severe) |