【判断题】开尔文提出不能从单一热源吸热做工而不产生其他影响。()
【单选题】All the parents worry about the() of TV on their children.
【单选题】—Is it that Jack often plays computer games makes his parents worry about him ? —Yes , I think so .
【单选题】Parents worry about violence on television because it may convince children that violence is an acceptable solution for conflict.
【单选题】1953年,Watson和Crick发现了
【单选题】( )是居住区的次要道路,用以解决居住区内部的交通联系。道路红线宽度一般为 10~14m 。