Please maintain a safe distance from the edge.

To keep in a specified state or condition.
We must maintain order.
Please maintain silence here.
They maintain their friendship.
maintain order
maintain silence
maintain contact
keep
preserve
uphold
The mechanic will maintain the company's fleet of trucks to ensure they are always in good working order.

To keep in a specified state or condition, often by providing necessary support or resources.
We must maintain our friendship.
Please maintain silence in the library.
They maintain a clean house.
maintain order
maintain contact
maintain control
preserve
uphold
sustain