| critical(adjective, hard, direct, tough, severe) |
| pressing(adjective, hard, direct, tough, severe) |
| vital(adjective, severe, heavy, important) |
| imperative(adjective, strong, firm, prompt) |
| crucial(adjective, tough, severe, heavy) |
| exigent(adjective, hard, tough, firm, difficult) |
| importunate(adjective, characteristic, hard, tough, continue) |
| instant(adjective, direct, prompt, importance) |
| essential(adjective, severe, important, significant) |
| serious(adjective, hard, tough, severe, difficult) |
| earnest(adjective, characteristic, strong, enthusiastic) |
| weighty(adjective, clear, hard, great, tough) |
| crying(adjective, firm, informal, prompt) |
| burning(adjective, firm, informal, prompt) |
| momentous(adjective, clear, tough, severe) |
| dire(adjective, severe, firm, prompt) |
| significant(adjective, clear, tough, severe) |
| paramount(adjective, direct, prompt, important) |
| primary(adjective, significant, substantial, valuable) |
| chief(adjective, great, significant, substantial) |