单句写作 （1） The businessman 　　　　 　　　　 　　　　（证明是）kind and generous. （2） 　　　　 　　　　 　　　　 　　　　 　　　　 （已经得到证实） eating vegetables in childhood helps to protect you against serious illnesses in later life. （3） —Why was Professor Smith unhappy recently? —Because the idea he stuck to 　　　　 　　　　（证明是错误的）.

proved to be

It has been proved that

proved wrong