单项选择题
A．twins can help each other B．twins share each other's emotion C．twins are able to understand each other in a private language D．twins communicate less with their parents
A．They can only understand their own private language. B．They communicate with outsiders less than non-twins. C．There is little stimulation for them. D．Adults don' t like to talk with them.
A．twins understand each other very well B．twins are slow to learn to talk C．twins are unlikely to do less well at school than other children D．there exists more communication between twins