The mansion has extensive grounds.

这大厦四周的庭园广阔。

"It is often a roofed, arcaded open gallery on an upper story overlooking a court, though it can also be a separate arcaded or colonnaded structure."

往往在房子的顶层设带拱顶的,可以俯瞰庭园的敞廊,尽管也可以的带拱顶的或带廊柱的结构。