leave someone to their own devices

leave someone to do as they wish without supervision

让…自行其是，听任…自行决定

leave to (one's) own devices

To allow to do as one pleases

听任某人自行其事：允许某人按自己的意愿做事

left the child to her own devices for an hour in the afternoon.

允许孩子在下午有一个小时的自由支配时间