It does work like this:alexius wrote:It should work like this.
Click (nothing selected) -> shift-click: all samples between click and shift-click are selected.
Double click on an audio clip - the audio clip is selected.
Click and drag along one or more tracks, the region spanned by the drag is selected.
Click on a label text box - the labelled region in the track that has focus is selected.
Click near the end of a selection and drag - the selection can be adjusted.
Shift + click. If there is a selection the end closest to the click position will move to the click position. If there is not a selection then a selection will be made between the playback cursor position and the click position.
Selections can also be adjusted via the keyboard or using the Selection Toolbar.
For further information see here: http://manual.audacityteam.org/man/Audacity_Selection