acid

sulphuric|hydrochloric|nitric|carbolic|citric|lactic|nucleic|amino acid: 硫|盐|硝|碳|柠檬|乳|核|氨基酸 王水是意译: Aqua regia is a mixture of nitric [含氮的] and hydrochloric [含氢和氯的] acid concentrations [浓缩物], usually one portion of the former by volume to three portions of the latter [不是later，多个t]. The alchemists [炼金术士] gave this mixture its name (literally [按字面意思], "royal water") due to its ability to dissolve [溶解] gold and other so-called noble metals [贵金属]. alkali/base: 碱, salt: 盐/食用盐; ammonia: 氨水

The 'al-' part of the word in Arabic [阿拉伯语] is the definite artile [定冠词] like 'the' in English. alchemist: the 化学家。alcohol: the kuhl/kuhul (essence of wine, spirit [烈酒]). Kohl is a cosmetic used around women's eyes. "一般来说睫毛膏的成分中不含酒精"，我怀疑最早是含的。"文艺复兴早期的贵妇人会使用含有醋、砷、氢氧化物以及碳酸盐的化妆品。" They are crazy.

Vinegar comes from the French phrase 'vin aigre,' which means sour wine. The wine tastes vinegary. "Sour as vinegar" is an idiom [习语]. Vinegar is sour. Don't eat it recklessly [鲁莽地].

Yoghurt (in Turkish yoghurut – curdled [结成凝乳] milk) is the most well-known and popular fermented [发酵] dairy product. It is produced with the help of selected lactic acid bacteria. Kefir [酸牛乳酒] is a fermented milk similar to yoghurt. It is one of the oldest cultured [grow bacteria] milk products in existence, enjoying widespread popularity in Russia and the Caucasus [高加索]. The word kefir comes from a language of the Caucasus, where it has been drunk since at least ancient times. Soured milk, similar to home-produced milk, is produced in dairy industrial plants by adding a culture of several types of lactic acid bacteria, the main one being Streptococcus lactis, to pasteurised [巴斯德] milk. Sour cream's history dates back to the first half of the 20th century, and is associated with the cooking traditions of Eastern Europe, Germany, Ukraine and Russia. Originally, making sour cream involved allowing fresh cream to sour naturally. Today, commercial [商业的] sour cream can contain the addition of lactic acid, gelatin or guar gum [不解释，要学会跳着看，smurf化，stuff化]. Both yoghurt and soured milk contain up to three bacteria, although the most prominent [显著的、突出的] among the three is traditional kefir, as in addition to more than a hundred microorganisms, it also contains yeast [酵母]. Kefir is considered to be the undisputed king of fermented dairy products.

Probiotic [益生菌, pro+biotic] yoghurt has grown in popularity in recent years. The main difference between regular and probiotic yoghurts is mainly the bacteria that they contain. The probiotic cultures [菌落] most commonly found in probiotic yoghurt are blah-blah-blah.

Lemons are acid fruits. 词典没明确说acid不能做表语，不过Some oranges have an acid flavor.好像更顺些。acid: sharp sour，尖酸。“真金不怕火炼”, 英语有acid test. 王水是浓盐酸与浓硝酸的混合物，能溶解黄金。The acid test of a teacher is 'Would you teach your own children?' It's an acid comment. The remark is acid. There's something acid in her tone.

acidity of the stomach: 胃酸(稀盐酸)过多。acid rain: 酸雨。不能说acid一定比sour酸，也许acid偏物质构成，sour偏味觉体验。acid的词源是: 'to be sour'

mellow: 香醇的; luscious: 香甜的; My mouth is full of saliva, I'm practically drooling. Salted garlic peanuts are savory. Monica's cheesecake is mealy (dry and powdery).

acknowledge

accord+knowledge. accord好几个意思，knowledge不遑多让，We gotta acknowledge the word acknowledge has many meanings.

Advice or acknowledgment of receipt is a postal service returning to the sender a form or card signed by the recipient. This is evidence that the letter was received, and these forms (or cards) are frequently seen with legal endorsements. It had existed under various names in some postal entities as early as the late 18th century, and was adopted by the GPU General Postal Union in 1875, and again by its successor, the UPU Universal Postal Union in 1879.

acquaint

quaint <= French(clever) <= Latin(known). acquaint: to know. 但quait: unusual and attractive. “古往今来,以讹传讹,好事者竟故意的弄出这古迹来以愚人。” ——《红楼梦》

在TBBT里，Sheldon called Leonard and Raj friends, and Howard a "treasured acquaintance". 最后一集他领诺贝尔奖时致辞：…I was there the moment Leonard and Penny met… [LDOCE][牛津]
1. I made his acquaintance at a party. [我无端地觉得这party比较高端]
2. Most people are nicer than you think on first acquaintance.

scrape (up) an acquaintance with sb: attempt to meet or befriend sb [somebody], esp [especially] because they may prove useful to one's needs, ambitions, or desires, 套瓷. "Well then, the soultion is simple. I shall befriend him. Kripke! … Well I think we're off to a terrific start."