Important (A1)

To help her make an important decision was her brother, who gave her support in such a hard time for her.

Essential (B1)

Getting answers to her relentless questions was essential for her, as their marriage has long been on the verge of collapse.

Crucial (B2)

The cigarette ash on the carpet has turned to be crucial evidence in the case under investigation.

Critical (B2)

Warning the resident population about an impending attack on the city by the enemy was critical.

Paramount (C2)

Raising awareness of citizens about a harmful impact of exhaust gases on the environment is of a paramount importantce, as it may foster more responsible civic behavior.

Fundamental (C2)

The first five years of children's life are claimed to be fundamental for their psycological development and should by no means be spent in a stressful setting.