question: letter:sms:wechat
choices.label: A B C D
choices.text: lights:tv:computer fan:electric fan:air conditioner cold dish:hot dish:staple food pager:phone:mobile
explanation: the functions of "letters", "sms" and "wechat" are the same and can be used for communication. "lights", "tvs" and "computers" are both household appliances. the functions of "lights" are lighting, which is different from that of "tvs" and "computers". "fan", "electric fan" and "air conditioner" have the same function and can be used to cool down. "cold dish" and "hot dish" are both dishes, and "staple food" is not the same as "cold dish" and "hot dish". a "mobile phone" is a type of "telephone".
relation: letter sms wechat R2.6
relation: lights tv computer R2.6
relation: fan electric fan air conditioner R2.6
relation: cold dish hot dish R2.6
relation: mobile phone R2.2