明天就要交了，可这是怎么回事？求大神帮忙！

unit Unit1;
interface
uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, StdCtrls;
type
TForm1 = class(TForm)
Button1: TButton;
Button2: TButton;
Button3: TButton;
Button4: TButton;
Button5: TButton;
procedure Button1Click(Sender: TObject);
procedure Button3Click(Sender: TObject);
procedure Button4Click(Sender: TObject);
procedure Button2Click(Sender: TObject);
private
{ Private declarations }
public
{ Public declarations }
end;
var
Form1: TForm1;
implementation
uses Unit2, Unit3, Unit4, Unit5;
{$R *.dfm}
procedure TForm1.Button1Click(Sender: TObject);
begin
Form2.ShowModal;
end;
procedure TForm1.Button3Click(Sender: TObject);
begin
Unit3.Form3.ShowModal;
end;
procedure TForm1.Button4Click(Sender: TObject);
begin
Unit4.Form4.ShowModal;
end;
procedure TForm1.Button2Click(Sender: TObject);
begin
Unit5.Form5.ShowModal;
end;
end.

@351317878

有人么