部分

This year's grain output has slumped because of natural disasters in some areas.

Her argument falls into three parts.

part and parcel (of); important part; major component

a small part/portion (of)

various parts of the body

first/second half

theoretical/practical part

best/better/greater part (of)

first part

an integral/inalienable part (of)

selected sampling

recover part of the embezzled/bribe money

account for a large portion/share (of); make up a large section (of)

take/assume part of the blame/responsibility