单项选择题A.Planktons are too small to be seen.B.Most planktons have transparent tissues.C.Most planktons are practically invisible to predators.D.Planktons are fascinating organisms.
单项选择题A.Four contestants failed to win prizes.B.The man ate during the show.C.The woman missed the show.D.Five contestants won cars.
单项选择题A.The lack of a real form of government structure.B.The creativeness of Eskimos.C.The excitement of a legal system with strict laws.D.The strong judicial powers of a headman.
单项选择题A.A camera.B.A film.C.Photo.D.Picture.
填空题smoke