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1 graze

1 : to feed on growing herbage, attached algae, or phytoplankton
2 : to eat small portions of food throughout the day
transitive verb
1 a : to crop and eat in the field b : to feed on the herbage of
2 a : to put to graze b : to put cattle to graze on
3 : to supply herbage for the grazing of
[M-W's Col. Dic.]

I think "crop" here means to harvest which means it involves humans. Which crop is eaten in the field after being harvested?

2 stock
transitive verb
1: to make (a domestic animal) pregnant
2: to fit to or with a stock
3: to provide with stock or a stock : supply <stock a stream with trout>
4: to procure or keep a stock of <our store stocks that brand>
5: to graze (livestock) on land
[M-W's Col. Dic.]

"on land" - Where else would livestock graze other than land, in the air?

Please help me with the above questions. Thank a lot.
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I think "crop" here means to harvest which means it involves humans.-- No, it does not. See the [url=http://www.onelook.com/?w=crop&ls=a ]QUICK DEFINITIONS[/url] on the left of the linked screen.

"on land" - Where else would livestock graze other than land, in the air?-- See [url=http://dictionary.reference.com/browse/land?r=66 ]DEFINITION #4[/url].
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Thank you, Mr Micawber.

"to graze and eat in the field" - Does this definition 'let feed in a field or pasture or meadow' fit the context? Please let me know.
Yes, that's good.
Thank you.
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