| sad(adjective, hard, difficult, complex, inexpedience) |
| punishing(adjective, hard, difficult, complex) |
| thorny(adjective, hard, difficult, complex) |
| operose(adjective, hard, difficult, complex) |
| serious(adjective, bad, hard, difficult, offensive) |
| toilsome(adjective, hard, difficult, complex) |
| grave(adjective, hard, difficult, complex) |
| heartrending(adjective, hard, difficult, complex) |
| rough(adjective, bad, hard, difficult, offensive) |
| sticky(adjective, hard, difficult, complex, embarrassing) |
| complex(adjective, hard, difficult) |
| harrowing(adjective, severe, miserable, wretched, anguished) |
| knotty(adjective, hard, difficult, complex) |
| problematic(adjective, hard, difficult, complex) |
| stressful(adjective, hard, difficult, complex) |
| taxing(adjective, hard, difficult, complex) |
| backbreaking(adjective, hard, difficult, complex) |
| complicated(adjective, hard, difficult, complex) |
| hefty(adjective, hard, difficult, complex) |
| intricate(adjective, hard, difficult, complex) |