diff --git a/Doc/reference/expressions.rst b/Doc/reference/expressions.rst
--- a/Doc/reference/expressions.rst
+++ b/Doc/reference/expressions.rst
@@ -430,12 +430,28 @@
 
 .. method:: generator.throw(type[, value[, traceback]])
 
-   Raises an exception of type ``type`` at the point where generator was paused,
+   Raises an exception at the point where the generator was paused,
    and returns the next value yielded by the generator function.  If the generator
    exits without yielding another value, a :exc:`StopIteration` exception is
    raised.  If the generator function does not catch the passed-in exception, or
    raises a different exception, then that exception propagates to the caller.
 
+   In typical use, this is called with a single exception instance similar to the
+   way the :keyword:`raise` keyword is used.
+
+   For backwards compatibility, however, the arguments follow a convention from
+   older versions of python.  ``type`` can be an exception class or an exception
+   instance, and ``value`` can be const:`None`, an exception instance, a single
+   argument or an argument tuple to be passed to the exception class constructor.
+   If provided, the ``tb`` argument is used for the raised exception, otherwise
+   the excepition instance's :attr:`__traceback__` attribute is used.
+
+   Example::
+      try:
+          generator.send(foo())
+      except Exception as e:
+          generator.throw(e.with_traceback(None))
+
 .. index:: exception: GeneratorExit