The human story began around 65 million years ago，when animals first appeared on Earth.Over thousands of years，their bodies became almost human.Their brains became （1）

bigger

bigger

（big），and they learned how to use language，light fires and make tools.Modern human-people like us-developed （2）

from

from

these creatures about 100，000 years ago.Many scientists believe modern humans first appeared in Africa.By 20，000 B．C．，they had travelled and settled all over the world.They travelled farthest during （3）

the

the

Ice Ages，when most seas were frozen，leaving bridges of dry land， （4）

which

which

people could walk across.The first farmers on Earth lived in the Middle East.Around 9，000 B．C．，people （5）

found

found

（find） that grains of wheat and barley dropped on the ground grew and produced seeds， （6）

so

so

they cleared land and planted more seeds.By around 6000 B．C．，people in Southeast Asia had discovered how to grow rice.By 5000 B．C．，in Central and South America，people were growing （7）

potatoes

potatoes

（potato） and corn.Early peoples had to make the big discoveries-how to build homes，farm the land，communicate and protect （8）

themselves

themselves

（they）.The world we live in has been built on the work of past generations，and it is still changing today.As each year （9）

passes

passes

（pass），it becomes another chapter in our （10）

amazing

amazing

（amaze） history.