TPO 07-AGRICULTURE, IRON, AND THE BANTU PEOPLES - 英檢

1.
The proposed areas of the domestication of African crops lie in
a band that extends from Ethiopia across southern Sudan to
West Africa. Subsequently

The proposed areas 這怎麼翻?

2.
Africans had iron from a relatively early date, developing ingenious furnaces
to produce the high heat needed for production and to control the amount of
air that reached the carbon and iron ore necessary for making iron.

the amount of air that reached the carbon and
iron ore necessary for making iron

air 跟 reache reached the carbon and iron ore 有什麼關係? 不知道怎麼翻才順

3.
These people probably originated in eastern Nigeria.

Their migration may have been set in motion by an increase in population
caused by a movement of peoples fleeing the desiccation,
or drying up, of the Sahara.

Their migration may have been set in motion by an increase in population
是增加哪裡的人?
set in motion 要怎麼翻?

感謝回答

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