beast of burden

animal, such as a donkey, used for carrying heavy loads on its back 力畜, 役畜, 牲口（如驴）.

bear down upon, bear in mind, bear off, bear on, bear out, bear sth. in mind, bear up, bear with, bear-hug, bear/keep in mind, bearable, beard, bearded, beardless, bearer, bearing, bearish, bearlike, bearskin, beast, beastly, beat, beat down, beat off, beat sb into/to sth, beat time, beat up and down, beat-up, beater, beatific, beatifically, beatification, beatify, beating, beatitude, Beatles, beatnik, beau, Beaufort scale, Beaujolais,