| arduous(adjective, hard, tough, severe, difficult) |
| laborious(adjective, hard, tough, severe, difficult) |
| backbreaking(adjective, hard, tough, severe, difficult) |
| heavy(adjective, hard, tough, severe, difficult) |
| toilsome(adjective, hard, tough, severe, difficult) |
| appalling(adjective, awful, terrible, horrible, afraid) |
| tiring(verb, adjective, hard, tough, severe) |
| grievous(adjective, awful, terrible, horrible, painful) |
| harrowing(adjective, awful, terrible, horrible, painful) |
| gruelling |
| trying(verb, adjective, hard, tough, difficult) |
| fatiguing(adjective, hard, tough, severe, difficult) |
| painful(adjective, hard, tough, severe, difficult) |
| woeful(adjective, awful, terrible, horrible, painful) |
| ghastly(adjective, bad, awful, terrible, disgusting) |
| severe(adjective, hard, tough, difficult, harsh) |
| hard(adjective, severe, difficult, harsh, heavy) |
| exhausting(adjective, hard, tough, severe, difficult) |
| strenuous(adjective, hard, tough, severe, difficult) |
| cruel(adjective, awful, terrible, horrible, painful) |