Unclued lights, five of two words and two pairs, have something in common. Elsewhere, ignore one accent.

Across

1 Keep bearing left for Great Lake (5)
11 Mule is slaughtered for food (6)
12 Delving into information, understands about saving (7, two words
14 800 in circle, enormous (5)
15 In the country, must run at first over mountain (5)
16 Boil may come into view, with light (6)
21 Consume a lot of meat, in total (7, two words)
23 Land in Scotland picked up, not hard (4)
25 Original Dutch tongue (4)
27 A long period in Chinese epic (7)
29 With knife, son carved hairy boot (8)
33 At...