| fussy(adjective, tough, difficult, problematic, trying) |
| gloomy(dull, hard, severe, offensive, boring) |
| grim(tough, problematic, trying) |
| grueling(adjective, hard, tough, difficult, awkward) |
| harassing(hard, severe, offensive, distressing, upsetting) |
| harsh(adjective, hard, severe, rough, difficult) |
| hefty(adjective, dull, heavy, boring, tedious) |
| interminable(adjective, dull, flat, stupid, dead) |
| invidious |
| knotty(adjective, hard, tough, severe, rough) |
| labored(adjective, tough, severe, difficult, awkward) |
| long-drawn-out(adjective, dull, boring, dreary, endless) |
| muted |
| normal(adjective, ordinary, familiar, commonplace, everyday) |
| pestiferous |
| plain(adjective, dull, simple, ordinary, familiar) |
| ponderous |
| rough(adjective, hard, tough, severe, difficult) |
| rugged(adjective, hard, tough, rough, difficult) |
| severe(adjective, tough, difficult, awkward, grim) |