Displace the entity to follow a set of key-framed decompose transforms.
A transform includes a translation, rotation and scaling factor. A decomposed transform interpolates each translation, rotation and scaling element separately and recompose them into a transform afterward, this can lead to better interpolation in some cases at the cost of some performance.
To manually add a key frame: add the action to the target entity, then move the entity to the desired location for the key frame, then right click on the action's time block and select the Insert Key menu item.