词条主要来源于这个列表【A】，解释主要来源于这个网站【B】。欢迎各位补充。

aisle：（大型仓储）超市里放商品的排、走廊、客机里的过道（不确定这第一个a是否算是不发音的，也许ai就可以发i的音类似于pie？见美国版知乎【C】）

cnid-：与刺胞有关的（如水母等；来源于希腊语）

czar：沙皇（来源于斯拉夫语）

gn-：这里举几个例子

        gnarled：树（干/枝）扭曲的；多瘤/节的；手（指）粗糙的（可能来源于德语；注意g/k互换）probably a variant of knurled, from Middle English knar "knob, knot in wood, protruding mass on a tree" (late 14c.), earlier "a crag, rugged rock or stone" (early 13c.), from a general group of Germanic words that includes English knob, knock, knuckle, knoll, knurl. Gnarl (v.) "make knotty," gnarl (n.) "a knotty growth on wood," and gnarly (adj.)

        gnome：1. 生活在地下/土里的类似于小矮人的小精灵。"dwarf-like earth-dwelling spirit," from French gnome (16c.), from Medieval Latin gnomus, used 16c. in a treatise by Paracelsus, who gave the name pigmaei or gnomi to elemental earth beings, possibly from Greek *genomos "earth-dweller" (compare thalassonomos "inhabitant of the sea" - 与地中海贫血thalassemia有相同词根--海周边的血液病)

        gnome：2. 金言/警句。"short, pithy statement of general truth," 1570s, from Greek gnōmē "judgment, opinion; maxim, the opinion of wise men," from PIE root *gno- "to know." （这里gno-与know同源，再次注意g/k互换；类似互换还有十分常见的b/p如subscribe/subscription，以及f/ph/gh如sulfur/sulphur-一个相关讨论见【D】简单来说就是希腊语来源的ph为主德语及古英语来源的gh为主，还有b/v互换可能更多见于其他欧洲语言中如Avril在法语里就是April四月的意思--标准qwert键盘里把v和b紧挨着排列的原因？）

        gnomAD：人群基因组变异频率数据库。估计创造这个词的人/小组想借用nomad（游牧民族，现代人类随着历史发展逐渐扩散到世界的各个角落）的意思，外加不发音的g开头也符合gn-构词法（因此发音为no-mad，而不是gee-no-mad）。当然其全称是The Genome Aggregation Database【E】。

        gnostic：与知识相关的，尤其是神话中魂魄相关的知识。"relating to knowledge," especially mystical or esoteric knowledge of spiritual things, 1650s, from Greek gnōstikos "knowing, good at knowing, able to discern," from gnōstos "known, perceived, understood," earlier gnōtos, from gignōskein "learn to know, come to know, perceive; discern, distinguish; observe, form a judgment," from PIE *gi-gno-sko-, reduplicated and suffixed form of root *gno- "to know."（对比加上否定前缀a-的不可知论agnostic）

        gnu：南非一带像牛一样的羚羊（什么鬼。。。）ox-like South African antelope, 1777, gnoo, from Dutch gnoe, used by German traveler Georg Forster (1754-1794) to render Khoisan (Hottentot) i-ngu "wildebeest," from Southern Bushman !nu: (in which ! and : represent clicks打响舌).

h-：比较常见，如heir, herb, honest, honor, hour等

kn-；比较常见，如knee, knock, knot, know等

mnemonic：助记符。1753, "aiding the memory, intended to assist the memory;" 1825, "pertaining to the memory," a back-formation from mnemonics, or from a Latinized form of Greek mnēmonikos "of or pertaining to memory," from mnēmōn (genitive mnēmonos) "remembering, mindful," from mnēmē "memory, a remembrance, record, an epitaph; memory as a mental faculty," from base of mnasthai "remember," from PIE root *men- (1) "to think." The noun meaning "mnemonic device" is from 1858. Related: Mnemonical (1660s). （对比加上否定前缀a-的失忆症amnesia）

pneumon-/pneum-：肺，如肺炎pneumonia。pneumo- before vowels pneum-, word-forming element meaning "lung," from Greek pneumon "lung," from PIE root *pleu- "to flow," altered in Greek by influence of pnein "to breathe."

ps-：这里举几个例子

        psalm：赞美诗、圣诗、圣歌。Old English psealm, salm, partly from Old French psaume, saume, partly from Church Latin psalmus, from Greek psalmos "song sung to a harp," originally "performance on stringed instrument; a plucking of the harp" (compare psaltes "harper"), from psallein "play on a stringed instrument, pull, twitch" (see feel (v.)). Used in Septuagint for Hebrew mizmor "song," especially the sort sung by David to the harp. Related: Psalmodize; psalmody. After some hesitation, the pedantic （学究气的）ps- spelling prevailed in English, as it was in many neighboring languages (German, French, etc.), but English is almost alone in not pronouncing the p-.

        pseudo-：伪/假的，在科技词汇中比较常见，如伪科学pseudoscience，笔名pseudonym

        psi：希腊语中的一个字母Psi (/(p)saɪ/; uppercase Ψ, lowercase ψ; Greek: ψι psi [ˈpsi]) is the 23rd letter of the Greek alphabet and has a numeric value of 700.维基百科【F】

        psoriasis：牛皮癣。1680s, from medical Latin psoriasis, in Late Latin "mange, scurvy," from Greek psoriasis "being itchy," from psorian "to have the itch," from psora "itch, mange, scab," related to psēn "to rub" (see psilo-).

        psych-：与精神相关（对比与神经相关的neuro-），如心理学psychology等

ptero-：翼/羽毛的。before vowels pter-, word-forming element in science meaning "feather; wing," from Greek pteron "wing," from PIE *pt-ero- (source also of Sanskrit patram "wing, feather," Old Church Slavonic pero "pen," Old Norse fjöer, Old English feeer), from root *pet- "to rush; to fly."我最熟悉的词恐怕是翼龙pteranodon（家里小孩子小时候会说很多恐龙相关的单词，我跟着学了不少）

ptosis：（眼皮）下垂。1743, from Greek ptosis, literally "falling, a fall," also "the case of a noun," nominal derivative of piptein "to fall," from PIE *pi-pt-, reduplicated form of root *pet- "to rush; to fly." In English, especially of the eyelid.

who：常见词（不确定这第一个w是否算是不发音的，也许wh就可以发h的音，如whole，whore？）

wr-：十分常见，如write，wrong，wrist等等。

关于PIE：原始印欧语言/语系Proto-Indo-European language，见维基百科【G】

关于linux/unix里的GNU和GNOME：GNOME is a free and open-source desktop environment for Unix-like operating systems. GNOME was originally an acronym for GNU Network Object Model Environment, but the acronym was dropped because it no longer reflected the vision of the GNOME project.见维基百科【H】

最后，我很赞同【C】里得票最高的回答：

Sorry, but there are very few “rules” of pronounciation in English, and even those have exceptions. In general, we use ay to sound like say. Once in a while we might use just the a, like Jason, and even less often ai, Like in straight. Spelling in English is really messed up. Our grammar is easy, but our spelling is hard. This is because English is a Germanic language largely infiltrated by Latin, and we also borrow lots of other words we just find use for. We have plenty of words that are just French or Greek words, for example. Some of these end up with an anglicized pronounciation, like hypocrite, and some retain (ree-tayn) their original pronounciation like epitome.

You just need to practice with English speakers. Watch movies in English. Talk to people in English and ask them to correct you.

In some other language to English transliterations, such as Hebrew, ai or ay is prounounced “I.” But that doesn’t help you with English words.

参考文献

A. https://www.wordnik.com/lists/starts-with-a-silent-letter

B. https://www.etymonline.com/

C. https://www.quora.com/Is-there-any-rule-explaining-the-pronunciation-of-ai-in-words-I-know-a-boy-called-Jai-his-family-pronounces-his-name-as-rhyming-with-pie-I-later-met-someone-whose-business-name-is-Jaisyn-but-its-pronounced-like

D. https://ell.stackexchange.com/questions/74713/why-is-a-ph-or-gh-used-instead-of-an-f-in-commonly-used-english-words-like

E. https://gnomad.broadinstitute.org/

F. https://en.wikipedia.org/wiki/Psi_(Greek)

G. https://en.wikipedia.org/wiki/Proto-Indo-European_language

H. https://en.wikipedia.org/wiki/GNOME