She felt unequal to the task she had set herself.

她觉得难以完成给自己定下的任务。

《牛津词典》

To tackle the unequal income distribution caused by the monopoly power, the key task is to establish the system of power restriction.

要根治权力垄断造成的收入再分配不公，首要的任务是要建立权力制约体制。

youdao

Internal austerity measures, including salary cuts and redundancies, proved unequal to the task of saving the bank, as the value of its assets continued to fall.

BBC: Laiki Bank: The Cyprus bank staff hit worst of all

But gradually there grew to be far too many of us, and our communities became too large and disparate for us to be able to feel a part of them, and our technologies were unequal to the task of drawing us together.

FORBES: Are You Being Followed By Helicopters?