在…上做拱成拱形
Overarch \O`ver*arch"\, v. t. & i. To make or place an arch over; to hang over like an arch. ``Brown with o'erarching shades.'' --Pope.
overarch v 1: be central or dominant; "This scene overarches the entire first act" 2: form an arch over; "Big rocks overarch the stream" [syn: {arch over}]