These words all describe a strong, unpleasant taste or smell.以上各词均形容味道或气味强烈、令人不适。
bitter(of a taste or smell) strong and usually unpleasant; (of food or drink) having a bitter taste指（味道或气味）强烈的、令人不适的，（食物或饮料）味苦的
pungent(of a smell or taste) strong and usually unpleasant; (of food or smoke) having a pungent smell or taste指（气味或味道）强烈的、令人不适的，（食物）味苦的，（烟）呛人的、刺鼻的：◆the pungent smell of burning rubber烧橡胶的刺鼻气味
sour(of a taste) bitter like the taste of a lemon or of fruit that is not ripe; (of food or drink) having a sour taste指（味道）酸的，（食物或饮料）有酸味的：◆Too much pulp produces a sour wine.过多的果肉会让酒变酸。
acrid(of a smell or taste) strong and unpleasant; (of smoke) having an acrid smell指（气味或味道）刺激的、难闻的，（烟）呛人的、刺鼻的：◆acrid smoke from burning tyres燃烧轮胎产生的熏烟
sharp(of a taste or smell) strong and slightly bitter; (of food or drink) having a sharp taste指（味道或气味）强烈而略苦的、刺鼻的，（食物或饮料）味苦的、辛辣的：◆The cheese has a distinctively sharp taste.这奶酪味道很冲。
acid(of a taste or smell) bitter, like the taste of a lemon or of fruit that is not ripe; (of food or drink) having an acid taste指（味道）酸的，（气味）有刺激性的，（食物或饮料）有酸味的
which word?词语辨析
A bitter taste is usually unpleasant, but some people enjoy the bitter flavour of coffee or chocolate. No other word can describe this flavour. A sharp or pungent flavour is more strong than unpleasant, especially when describing cheese. Sharp, sour and acid all describe the taste of a lemon or a fruit that is not ripe. An acrid smell is strong and unpleasant, especially the smell of smoke or burning, but not the smell of food. * bitter 指味道通常为苦的、令人不快的，有人却喜欢咖啡或巧克力的苦味。没有其他词可用来形容这种味道。sharp 或 pungent 主要强调味道强烈而非令人不快，在描述奶酪的味道时尤其如此。sharp、sour 和 acid 均形容柠檬或未熟水果的酸味。acrid 指气味强烈而令人不快，尤指烟味或燃烧产生的气味，但不用来形容食物的气味。