| knotted(adjective, hard, complex) |
| strenuous(adjective, dull, hard, great, tough) |
| cruel(adjective, hard, nasty, harsh, complex) |
| daedal(adjective, hard, complex, involved, complicated) |
| toilful(adjective, hard, complex, awkward, demanding) |
| unbearable(adjective, hard, complex) |
| finicky(adjective, tough, harsh, meticulous, fussy) |
| awkward(adjective, tough, rough, harsh, delicate) |
| delicate(adjective, hard, awkward, uneasy, tricky) |
| exacting(adjective, dull, hard, tough, severe) |
| fussy(adjective, hard, tough, harsh, particular) |
| fastidious(adjective, tough, careful, scrupulous, particular) |
| formidable(adjective, hard, tough, severe, evil) |
| heavy(adjective, dull, hard, tough, severe) |
| abstruse(adjective, hard, obscure, strange, uncertain) |
| exhausting(adjective, dull, hard, tough, awkward) |
| perplexing(adjective, hard, fancy, obscure, delicate) |
| obscure(adjective, hard, strange, uncertain, complex) |
| unmanageable(adjective, tough, terrible, wild, awkward) |
| critical(adjective, hard, crabby, cranky, meticulous) |