| unfeasible beyond one impracticable impractical infeasible inoperable insuperable insurmountable too much for unachievable unattainable uncompassable undoable uneffectible unnegotiable unperformable unrealizable unsurmountable unworkable |
| unrealizable beyond one impracticable impractical infeasible inoperable insuperable insurmountable too much for unachievable unattainable uncompassable undoable uneffectible unfeasible unnegotiable unperformable unsurmountable unworkable |
| insurmountable beyond one impassable impracticable impractical indomitable inoperable insuperable invincible too much for unachievable unattainable uncompassable unconquerable undoable uneffectible unnegotiable unperformable unrealizable unsurmountable unworkable |