SunflowersLw AI Practice & Learning AppsAI 练习与学习应用.
Get better by doing — with AI feedback on every rep.在做中变好——每一次练习都有 AI 反馈。
Practice-first products that use AI to help you improve a skill safely: paper-trade the markets, rehearse spoken English judgement-free, or get quizzed on your own code changes when you ask. Each is built to give feedback on every attempt, not just deliver content.以练习为先的产品，用 AI 帮你安全地提升一项技能：在市场上做模拟交易，不计评判地演练英语口语，或者在你提出请求时就你自己的代码改动接受提问。每一个都是为了对每一次尝试给出反馈而打造的，而不只是交付内容。
Tradrill
Fintech · Simulator金融科技 · 模拟器Learn to read technology stocks: transmission-chain notes, a paper-trading simulator, and behavioral reports. No stock picks.学会读懂科技股：传导链笔记、模拟盘和行为报告。不荐股。
- Trace how a tech event reaches a listed company, with a source on every hop追踪科技事件如何传导到上市公司，每一跳都附可打开的来源
- Trading Twin reports on your simulated fillsTrading Twin 针对你的模拟成交出具行为报告
- Paper-trade your thesis on a virtual $100,000 desk (US and HK stocks, delayed quotes)在虚拟 10 万美元的模拟盘上检验自己的判断（美股与港股，延迟报价）
FluentDojo
Language · Voice语言 · 语音A real-time voice AI partner for spoken English, in the browser.浏览器里的实时语音 AI 英语口语搭档。
- Practice spoken English with an interactive AI voice partner any time随时与 AI 实时语音伙伴展开自由对话，无需预约外教
- Continuous voice conversation you can interrupt, with push-to-talk, typing, and live captions with translation随时打断的连续语音对话，支持按键说话、文字输入与带翻译的实时字幕
- After each call: fluency, grammar and vocabulary scores plus rewrites. Per-word pronunciation scores in read-aloud practice.通话后总评：流利度、语法、词汇打分与改写；发音评分在朗读练习里按单词给分
covate
Dev Tool · MCP开发者工具 · MCPOpen-source MCP learning sidecar and persistent debugging memory for AI assistants.面向 AI 助手的开源 MCP 学习边车与持久化调试记忆。
- Quizzes you on your own AI-assisted changes when you ask在你提出时，就你自己的 AI 辅助代码改动出题考你
- Persistent debugging memory across coding sessions跨会话持久化记录调试思路与排错路径，避免重复踩坑
- MCP sidecar that plugs directly into Claude Code, Codex, and modern AI tools无缝接入 Claude Code、Codex 及标准 MCP 协议编程宿主
FAQ常见问题
What AI apps help you practice a skill risk-free?哪些 AI 应用能帮你零风险地练习一项技能？
Tradrill lets you test a thesis on a virtual paper-trading desk (no real money at risk), FluentDojo lets you practice spoken English with a real-time AI voice partner, and covate quizzes you on your own code changes to lock in what you just learned.Tradrill 让你在一个虚拟的模拟交易台上检验一个论点（没有真实资金处于风险之中），FluentDojo 让你与一个实时的 AI 语音伙伴练习英语口语，covate 就你自己的代码改动向你提问，以巩固你刚刚学到的东西。
How is "learn by doing" better than watching tutorials?「在做中学」比看教程好在哪里？
These tools give feedback on each attempt — a trade decision, a spoken sentence, a code change — so you build durable skill through reps and correction instead of passive watching.这些工具对每一次尝试都给出反馈——一次交易决策、一个口头说出的句子、一处代码改动——于是你通过反复练习和纠正建立起扎实的技能，而不是被动观看。
Which of these is free?其中哪些是免费的？
FluentDojo and covate’s open-source MCP are free to start; Tradrill is free today (Pro not on sale yet). Follow each link to its own site to begin.FluentDojo 和 covate 的开源 MCP 可以免费起步；Tradrill 目前是免费的（Pro 尚未开售）。点开各自的链接，到它自己的站点开始。