-
In
order to make your object stay still at a certain point along the path, you
need to make a flat (horizontal) section in your curve.
If a function curve does not move up or down,
then there is no change of value, and the
object remains motionless.
-
In
Track View, click Create
Key: 
-
Now
click on your Curve at the point where you want
your object to stop. This will create a key frame.
-
Now
choose the Move Keys tool (horizontal):
-
(This
button is part of a drop-down button)
-
Now
hold down SHIFT and Click and Drag your Key frame to the right to create a
copy.
-
Because
we are only moving it horizontally, the value of both key frames remains the
same.
-
Now
select all of your key frames and change their Tangent Types to Linear.
-
You
should now have something like this: