Нам должно быть выброшенными на какой-нибудь остров.
Howbeit we must be cast upon a certain island.
“But we must run aground on a certain island.”
But we must run aground on some island.”
Nevertheless, we must run aground on some island.”
However, we must run aground on a certain island.”
But we will be shipwrecked on an island.”
But we must be cast ashore on a certain island.