An immigration overhaul has long proven a complicated political task.

全面修订移民政策长期以来一直是一项复杂的政治任务.

Object formalism , it is an earnest political task that is placed before us.

反对形式主义，是摆在我们面前的一个严肃的政治课题。

It is a long-term and arduous political task to build the harmonious society.

构建和谐社会是长期而艰巨的政治任务。