sentences:

1.Insects would make it impossible for us to live in the world;they would devour all our crops and kill our flocks and herds, if it were not for the protection we get from insect-eating animals

(devour eat immoderately or greedily)

(flock a group of sheep or goats)

(herd a goup of domestic manmmals)

2.Spiders would never do the least harm to us or our belongings.

3.make a census of spiders in grass field in the south of England

(a periodic count of the population)