ponderous
adjective formal mainly disapproving uk/ˈpɒn.dər.əs/ us/ˈpɑːn.dɚ.əs/
（因重或大而）行动迟缓的，笨拙的
slow and awkward because of being very heavy or large
He had a slow and ponderous manner. 他的举止缓慢笨拙。
（书、讲话或写作风格）严肃而乏味的，呆板的，生硬的
If a book, speech, or style of writing or speaking is ponderous, it is boring because it is too slow, long, or serious.
The ponderous reporting style makes the evening news dull viewing. 沉闷的播音风格使晚间新闻看起来很乏味。