【多线程】疑问

过程time是实时汇报时间的。下面主程序就简化为整数加法吧。
只是运行总是不能如愿。我觉得是我对多线程的理解错了，希望有吧友能够帮忙看看怎么解决这类问题。主要是如何在不破坏主程序的情况下，实时汇报时间。
uses dos,windows,crt;
var i,j:integer;
tid:dword;
year,month,date,dow,hour,minute,second,hs:word;
procedure time;
begin
repeat
getdate(year,month,date,dow);
gettime(hour,minute,second,hs);
gotoxy(1,1);
writeln(year,' ',month,' ',date);
gotoxy(1,2);
writeln(hour,' ',minute,' ',second);
delay(1000);
until false;
end;
begin
clrscr;
createthread(nil,0,@time,nil,0,tid);
gotoxy(1,5);
write(1000+100);
end.

Windows XP SP3下由Free Pascal 2.0.4编译运行正常

主程序要死循环，
procedure timethread()
begin
while (true) do begin {死}
{线程中要做的事情}
sleep(1000); {休息1秒再从新循环}
end;
end;
{主程序}
begin
createthread(nil,0,@timethread,nil,0,tid);
while(true)do begin
{主程序中要做的事情;}
sleep(100); {这里要延时，如果不延时cpu会很疯狂}
end;
end.

uses dos,windows,crt;
var i,j:integer;
tid:dword;
year,month,date,dow,hour,minute,second,hs:word;
procedure time;
begin
repeat
getdate(year,month,date,dow);
gettime(hour,minute,second,hs); {输出日期}
gotoxy(1,1);
writeln(year,' ',month,' ',date);
gotoxy(1,2);
writeln(hour,' ',minute,' ',second); {输出时间}
delay(1000);
until false; {死循环}
end;
begin
clrscr;
createthread(nil,0,@time,nil,0,tid);
gotoxy(1,5);
write(1000+100); {简化后的主程序}
end.

uses dos,windows,crt;
var i,j:integer;
tid:dword;
year,month,date,dow,hour,minute,second,hs:word;
procedure time;
begin
repeat
getdate(year,month,date,dow);
gettime(hour,minute,second,hs);
gotoxy(1,1);
writeln(year,' ',month,' ',date);
gotoxy(1,2);
writeln(hour,' ',minute,' ',second);
delay(1000);
until false;
end;
begin
clrscr;
createthread(nil,0,@time,nil,0,tid);
gotoxy(1,5);
write(1000+100);
while true do;
end.

用TerminateThread终止线程的范例如下：
uses dos,windows,crt;
var tid:dword;
year,month,date,dow,hour,minute,second,hs:word;
hthread:hwnd;
procedure time;
begin
repeat
getdate(year,month,date,dow);
gettime(hour,minute,second,hs);
gotoxy(1,1);
writeln(year,' ',month,' ',date);
gotoxy(1,2);
writeln(hour,' ',minute,' ',second);
delay(1000);
until false;
end;
begin
clrscr;
hthread:=createthread(nil,0,@time,nil,0,tid);
gotoxy(1,5);
while not keypressed do;
terminatethread(hthread,0);
while true do;
end.
//程序运行后每秒更新一次时间，直到用户按下一个键

原来写两个begin end就可以多线程