Post offoce box POB信箱
a post office box邮政局
post office box邮箱;邮政箱;邮政信箱
post office box mailbox邮筒
pob post office box邮政信箱
post-box筒型;设在路旁供寄信用的柱墩状箱
private post office box私用邮政信箱
Post Office Box Delivery System邮政信箱派递系统
N-COUNT（可数名词） A postbox is a metal box in a public place, where you put letters and small parcels to be collected. They are then sorted and delivered. Compare . 邮箱 [英国英语]
And with a trembling hand, he dropped the letters into the postbox.
他颤抖的手把信投进了邮箱。