The (three-fields) system is an agricultural method in which one field (out of) (three) is (left) to lie fallow while the other two fields are being cultivated.

A．very critical
B．unpopular
C．very popular
D．very courteous

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B. Yes. We need a double room for this weekend.
C. Thank you, I’ d like to make a long distance call to New Zealand.
D. Sony. I don’ t think you can help us. Thank you anyway.