垂径定理的逆定理是正确的么？ 是正确的，可以证明
用英语写一封投诉信（内容如下），要求按照投诉信的格式 Dear manager：One month ago，bceause the recommendation of your salesperson，i bought a Japanese TV.But now，i'm afraid i will complain about it's bad quality.First，the picture is very unclear.And then，it doesn't have the voice sometimes.So，this TV not only doesn't take any happiness to us，but also take the big problem to us.I am the frequent customer of your shop，and like your message\"customer first，serve God\".Now，i want to change the TV.Or else，i would rather refund the money.I still keep the invoice.I am looking forward to your satisfied 自己翻译的 希望符合您的要求。
live alone和live lonely 哪个对？ 弟二个对的
