You can add a dissolve between two shots provided that there are a sufficient number of underlying handles.
To add a dissolve between two shots:
Click Editing, and then click Edit.
The Edit menu appears.
(a) Dissolve menu button (b) Dissolve button (c) Duration slider
Place the positioner on or near the transition to which you want to add a dissolve.
Enable Dissolve, and then drag the Dissolve slider to set the dissolve duration.
To edit the shape of the Dissolve curve, see Editing Dissolves.