A group of aliens has come to Earth to learn about its population, customs, etc. To avoid detection, they have taken on human form which gives them

　　A group of aliens has come to Earth to learn about its population, customs, etc. To avoid detection, they have taken on human form which gives them

　　A group of aliens has come to Earth to learn about its population, customs, etc. To avoid detection, they have taken on human form which gives them