A small example of why context matters: 下课 (xià kè) is a class ending; 放学 (fàng xué) is school finishing for the day; 放假 (fàng jià) is having a holiday or break. 今天几点放学? asks what time school finishes today; 什么时候放假? asks when the break starts.
I build Lingo Bear, an AI-assisted English–Mandarin web tool. I am offering the existing Explore Pro monthly plan to adults who repeatedly need explanations of everyday phrases at home: US$19/month plus checkout tax, automatically renewing until canceled. This is a paid product offer, not a research interview.
What you get: enter your own text/photo/voice question, generate a contextual bilingual explanation, explore connected learning cards, and revisit what you saved. An account, history and saving favorite cards are already available on Free; the paid capability is own-question generation and deeper exploration. Fair-use, rate and safety limits apply.
Read the prepared example without an account, including school clubs vs hobby classes vs tutoring: https://app.lingo-bear.com/for/bilingual-families . It demonstrates the format; it is not a private-generation trial. AI can make mistakes and needs adult review. This is not tutoring, a structured course or an app for children to use alone. No fluency or educational outcome is guaranteed.
To purchase through this offer: reply “monthly” with one non-sensitive routine you want to use it for. I will confirm fit and these terms in writing before you pay, without a sales call or a multi-day interview. Then use https://app.lingo-bear.com/pricing and choose Monthly Explore Pro; check that checkout says US$19 billed monthly plus tax, not the annual plan.
Delivery and acceptance: access should activate after successful payment. Within 24 hours of your purchase message, I will help check that you can ask your own question, receive a relevant bilingual answer, open a connected card and return to saved history/favorites. You decide whether that agreed workflow was delivered; payment alone is not acceptance.
If access or the agreed core workflow fails, contact bigkey.cn@gmail.com. I will respond within 24 hours; if I cannot provide the agreed core value, I will arrange a full refund of the first charge. This is a remedy for failure to deliver, not an unrestricted free trial. You can cancel renewal in the billing portal; normal cancellation keeps access through the paid period. No custom development or extra support fee is included. Please do not post children's identities, private messages, photos or school details.