Glaciers pluck out giant blocks of rock when forming cliffs and basins.

Here's how it works:

* Plucking: As a glacier moves, meltwater seeps into cracks and crevices in the bedrock. This water freezes and expands, putting pressure on the rock. Eventually, the ice breaks off large chunks of rock, a process called plucking.

* Erosion: The plucked rock fragments are then transported by the glacier, further eroding the landscape.

* Cliffs and Basins: The plucking process creates steep cliffs, while the removal of rock by the glacier forms basins or depressions in the land.

So, in summary, glaciers use plucking to carve out large blocks of rock, which then contribute to the formation of cliffs and basins.