th thumb 拇指 [Card #13; 字卡第13張: 第1個單字, 字母組合發音 th]

Soft /th/ sound (voiceless: θ)
• Initial position(首):thank, thaw, thrall, thwart, therapy, theft, thief, three, theme, theater, theory, thesis, thesaurus, thick, think, thin, thing, thimble, thigh, thyroid, thirst, third, thirteen, thirty, thousand, Thursday, thermal, thermos, thermostat, thermometer, thorough, thorn, thought, thousand, thud, thug, thunder, thumb, thump
• Medial position(中):author, authority, authentic, athlete, anthem, method, menthol, nothing, something, anything, filthy, sympathy, telepathy, empathy, empathize, enthusiasm, marathon, mathematics, arithmetic, synthetic, aesthetic, anesthesia, anthology, southeast, northwest, cathedral, catholic, ethic, ethnic, strengthen, parenthesis, pathetic, panther, birthday, bathroom, bathtub, ethos, ether, ethal, lethal, lethargic, orthopedic, orthodox, hypothesize, ruthless, stethoscope
• Final position(尾):bath, path, math, aftermath, labyrinth, wrath, faith, width, filth, myth, length, depth, strength, broth, froth, cloth, moth, month, mammoth, both, oath, growth, south, mouth, booth, tooth, teeth, heath, sheath, wreath, beneath, underneath, death, health, wealth, stealth, sloth, growth, forth, north, worth, berth, birth, girth, mirth, earth, dearth, Ruth, truth, youth, warmth, swath
fourth*, fifth*, sixth*, seventh*, eighth*, ninth*, tenth*, eleventh*, twelfth*, thirteenth*, fourteenth*, fifteenth* … twentieth* (* 除了 1/2/3 是不規則的變化,在數字尾巴加上 th 即可成為序數,字尾是 y 的,去 y 加 ieth。)

Hard /th/ sound (voiced: ð)
• Initial position(首):thus, than, the, this, that, these, those, there, their, they, them, then, thence, though
• Medial position(中):bother, other, another, smother, brother, mother, father, farther, further, gather, rather, slather, slither, feather, leather, weather, whether, together, either, neither, wither, within, without, clothing
• Final position(尾):bathe, breathe, blithe, loath, soothe, smooth, with