| challenge(noun, dispute, question, test, trial) |
| clamorous(adjective, hard, tough, firm, difficult) |
| close |
| contrary(adjective, severe, difficult, cross, persistent) |
| desiring(verb, adjective, avid, greedy, wanting) |
| detailed |
| effortful(adjective, tough, severe, difficult, harsh) |
| exhausting(adjective, dull, hard, tough, difficult) |
| firm(adjective, persistent, obstinate, insistent, dogged) |
| heavy(adjective, dull, tough, severe, rough) |
| impatient(adjective, keen, violent, anxious, wait) |
| insistent(adjective, hard, tough, firm, difficult) |
| mean(adjective, hard, severe, rough, difficult) |
| narrow |
| nit-picking(adjective, severe, sharp, rough, cross) |
| obdurate(adjective, severe) |
| painful(hard, tough, severe, difficult, harsh) |
| petitioning(verb, requesting) |
| punishing |
| requesting(verb, requesting) |