bum

Compared meaning: low quality, badly made (adjective).

比较义项：质量低劣、劣质的（形容词）。

• cheap

  Cheap suggests low quality that comes from being made or sold inexpensively; common and everyday, used for goods, food or materials, often implying poor value for money.

  cheap强调因制作或售价低廉而质量差，是常见的日常用词，多形容商品、食物或材料，常暗示价格虽低但物有不值。

  The cheap plastic toy broke apart on its very first use.

  这个廉价的塑料玩具第一次使用就散架了。

• bum 本词

  Bum is informal, mainly American slang for something worthless or badly made; used casually about objects, deals or situations, never in formal writing.

  bum是非正式的美式俚语，形容没有价值或做工低劣的东西，多用于随口谈论物品、交易或状况，不用于正式书面语。

  I bought a bum used car that broke down within a week.

  我买了一辆劣质的二手车，一周内就抛锚了。

• inferior

  Inferior is formal and often comparative, meaning lower in quality than something else; common in reviews, business and technical writing, frequently followed by 'to'.

  inferior是正式用词，常用于比较，意为质量比另一物差，多见于评论、商业和技术写作中，后面常接to。

  Critics said the sequel's special effects were inferior to the original.

  评论家说续集的特效比原作逊色。

• coarse

  Coarse describes low-quality material that feels rough or is roughly made, focusing on texture and craftsmanship rather than price or overall worth.

  coarse形容质地粗糙、做工粗劣的材料，侧重于触感和加工工艺，而不是价格或整体价值。

  The coarse fabric scratched her skin and frayed after one wash.

  这种粗劣的布料刮得她皮肤难受，洗一次就磨损了。

Cheap, bum, inferior, and coarse all mean poor quality. Bum is slang; coarse means rough material or bad craftsmanship; inferior is a formal comparison word; cheap means low quality from being inexpensive. Not compared: cheap's 'low price' sense, bum's 'homeless person' sense, coarse's 'rude' sense.

这几个词都能形容“质量差”，但语气和使用场合不同：bum是非正式俚语，coarse偏重材质粗糙、做工不精，inferior是正式的比较用词，cheap强调因便宜而质量不好。这里不比较cheap的“便宜的”（价格）义项，也不比较bum的名词“流浪汉”义项，也不比较coarse的“粗鲁的”（举止、语言）义项。