Completely useless notes: every one of sin 1° through sin 90° written out in radicals. The constructible angles come out clean — sin 3° is a single nested square root — while the rest need a cube root of a complex number to say at all, which is Gauss telling you the angle cannot be constructed with compass and straightedge. You are strongly suggested to memorise all ninety.
The second vocabulary set, worked out of HKDSE past-paper reading passages and grouped by paper. Several hundred entries, each with its part of speech, a Chinese gloss, and a remark carrying either a synonym or a sentence showing the word in use — frowned on, cast-offs, bicker, uber-chic, concession.
前往中环金钟的城展馆领取「城市景观摄影比赛」的优异奖——一张奖状与 500 元礼券。展览设在四楼，主办方把参赛作品印得极大且清晰，于是在自己的照片前留了影；随后细看公开组的获奖作品，从构图、色彩到画面的故事感都远在意料之外，一并记下路上遇见的那栋造型奇特的大楼。
素材第四辑【目标 & 意志】：自王勃「穷且益坚，不坠青云之志」起，分「形容目标志向」与「形容为目标努力」两路铺开成语表——鸿鹄之志、蹈厉之志、衔石填海、锲而不舍——每一类附作文构思，并以周恩来、司马迁、陈涉为例给出可直接套用的论证示例。
素材第三辑【旅行 & 自然】：按「描写旅行过程与感受」「形容旅行见闻」等类目铺开的成语表——沐露梳风、乘桴浮海、探奇穷异、千岩竞秀——生僻处逐条附释义，每一类再跟上作文构思与一整段写景示例，供游记与状物类命题取用。
A command-line Tic-Tac-Toe in Python whose whole game — the board, the input handling and the computer’s choice of move — fits in sixty-five lines once the code written purely for player experience is set aside. This post walks through the logic the opponent plays by, and links the full source on GitHub.
字蛛（font-spider）解析页面实际用到的字形，删掉其余的字形数据，把动辄二十余兆的开源中文字体压到可以真正上线的体积。本文记录它的安装与国内镜像源配置、woff2/woff/eot/svg 的生成能力，以及一条绕不开的限制——由 JavaScript 动态插入的元素与样式，它看不见。
议论文素材第二辑：延续同一体例的名句摘录，每则标注适用主题、出处，并附一段可直接拆用的作文示例，覆盖离别与重逢、脚踏实地、厚积薄发等常见命题方向。
议论文素材第一辑：十则名句摘录，每则都配齐适用主题、出处与整段作文示例——林清玄由离别写重逢的喜悦，李延寿以「良玉未剖，与瓦石同类」喻实践先于空想，钱锺书则说天下没有偶然，那不过是化了妆、戴了面具的必然。
The first vocabulary set, gathered while reading English news and opinion writing: phrases, nouns and adjectives laid out with their part of speech and a Chinese gloss — to contend with, throngs of pedestrians, vibrant, gravy train — and every entry set in bold carries its full Cambridge Dictionary definition underneath.
