free rein ---- 自由，随意（成语）

英文释义

(IDIOM) Complete permission to make decisions, spend money, and manage without any limits or supervision. (NOTE: "rein" is a cord used to control horses)

例句

The talented project manager agreed to take the difficult new project only if she was given complete free rein.

只要能够给予自由行事的权力，这位天才的项目经理就同意接受这个困难的新项目。