At the start of a cross-subject（语境补充词）/cross-subject/ challenge, Leo's team received a real case rather than a textbook（教科书）/'tekstbuk/ exercise. The opening evidence connected impress（印象、特征）/im'pres/, impression（印象、意念）/im'preʃәn/, improve（提高；改善）/ɪmˈpruːv/, inch（英寸）/ɪnʧ/, incredible（难以置信的）/in'kredәbl/, indeed（确实）/ˌɪnˈdid/, independent（独立的）/ˌɪndɪˈpɛndənt/, indicate（表明）/ˈɪndəˌkeɪt/, infection（传染、影响）/in'fekʃәn/, infer（推论出、推断）/in'fә:/, injury（伤害、侮辱）/'indʒәri/, inner（内部的、内心的）/'inә/, innocent（天真的人、笨蛋）/'inәsәnt/, and innovation（创新、改革）/.inәu'veiʃәn/. The links looked unusual, but each detail came from a witness, label（标签、称号）/'leibl/, form, or measurement（尺寸、度量）/'meʒәdmәnt/ in the case file. The team has already reviewed the complete plan.

A second folder added inquire（询问、问明）/in'kwaiә/, insect（昆虫、卑鄙的人）/'insekt/, insight（察看、洞察力）/'insait/, insist（坚持）/ˌɪnˈsɪst/, inspection（检验、检查）/in'spekʃәn/, inspire（使感动、激发）/in'spaiә/, instance（建议、情况）/'instәns/, instant（紧急的、立即的）/'instәnt/, institute（学会、学院）/'institju:t/, integrity（正直、廉正）/in'tegriti/, intelligent（聪明的、智能的）/in'telidʒәnt/, intend（打算）/ˌɪnˈtɛnd/, intense（非常的、强烈的）/in'tens/, and interrupt（中断）/.intә'rʌpt/. Some entries described people and places; others recorded objects, actions, or changing conditions. The students sorted each clue by time and source instead of forcing an early answer. The final choice was explained to everyone at the meeting.

The hardest set included intervention（插入、介入）/.intә'venʃәn/, investment（投资）/ˌɪnˈvɛstmənt/, involve（涉及；使参与）/ˌɪnˈvɑlv/, iron（铁）/aɪərn/, item（物品；项目）/ˈaɪtəm/, jam（果酱、拥塞之物）/dʒæm/, jaw（颚、颌）/dʒɒ:/, jazz（爵士乐、喧闹）/dʒæz/, jeans（牛仔裤）/dʒiːnz/, jog（轻推、轻撞）/dʒɒg/, joint（连接处、接合）/dʒɒint/, joy（快乐）/dʒɔɪ/, judge（评委；判断）/dʒʌdʒ/, and jungle（丛林、杂乱的一堆）/'dʒʌŋgl/. Leo checked spelling and context while a partner marked facts that could be tested. Mina, who led（lead的过去式和过去分词）/led/ the discussion（讨论）/dɪˈskʌʃn/, asked for clear evidence. Then the supervisor（管理者、监督者）/.sju:pә'vaizә/ said, “Do not hide an awkward clue merely because it weakens（削弱、减弱）/'wi:kәn/ your first idea.”

The last working board brought together junior（年少者、地位较低者）/'dʒu:njә/, justify（替...辩护、证明）/'dʒʌstifai/, kangaroo（袋鼠）/.kæŋgә'ru:/, kettle（茶壶、罐）/'ketl/, kindergarten（幼稚园）/'kindә.gɑ:tn/, kingdom（王国、领域）/'kiŋdәm/, kit（装备、工具箱）/kit/, label, lack（缺少）/læk/, lamb（羊羔；羊肉）/læm/, lamp（灯；台灯）/læmp/, landscape（风景、山水）/'lændskeip/, lantern（灯笼、提灯）/'læntәn/, and lap（膝盖、舔）/læp/. The group compared the four boards, removed repeated claims, and wrote（写下）/roʊt/ a short reason beside every decision（决定）/dɪˈsɪʒn/. If the first method fails, we can try another one. That rule helped them correct two mistakes without blaming a teammate（队友）/'ti:mmeit/.

They planned to check in（办理登记手续）/ʧɛk ɪn/, check out（办理退房；结账离开）/ʧɛk aʊt/, and set off（出发）/sɛt ɔf/ at safe times. Nobody would go on board（在交通工具上）/ɔn bɔrd/ without checking the notice in advance（提前）/ɪn ədˈvæns/. In case of（万一；如果发生）/ɪn keɪs əv/ trouble, one adult would be responsible for（对……负责）/bi riˈspɑnsəbəl fər/ contact while the student could apply for（申请）/əˈplaɪ fər/ official help. The completed record told（告诉）/toʊld/ a clearer story than the first draft. It did not pretend that every clue was equally important; it showed how disciplined reading, calm cooperation（合作、协力）/kәu.ɒpә'reiʃәn/, and a checkable（语境补充词）/checkable/ decision could turn a crowded case into useful（有用的）/ˈjuːsfəl/ action.