Ответ:

program z1;

var s1,s2,s3,s4: string;

begin

s1:='тестирование';

s2:=s1;

delete (s2,7,6);

s2[5]:=s1[2];

s2:=copy(s2,1,1)+'o'+copy(s2,3,4);

writeln (s2);

s3:=s1;

delete (s3,6,6);

insert ('о',s3,1);

insert ('в',s3,3);

insert ('р',s3,5);

writeln (s3);

s4:=copy(s1,8,2)+copy(s1,1,1)+copy(s1,9,1);

writeln (s4)

end.