Wait two task completes then print sonething

using (Task t1 = Task.Factory.StartNew(() =>
                          {
                              if (list.Count > 0)
                                  Console.WriteLine("Block begin");
                              for (int i = 0; i < 4; i++)
                              {
                                  if (list.Count > 0)
                                  {
                                      var firstItem = list.FirstOrDefault();
                                    // blah blah
                                      list.Remove(firstItem);
                                  }
                              }
                              bc.CompleteAdding();
                          }
                               ))

                       using (Task t2 = Task.Factory.StartNew(() =>
                           // blah blah))
                           Task.WaitAll(t1, t2);
                           Console.WriteLine("Block end");

Block begin
item 1
item 2
...
Block end

Block begin
Block end
item 1
item 2
...