The tides and currents of the river frequently shift mud and sand in the harbour.

But this fall, the currents of American immigration policy shifted yet again.

With the terrorist attacks of 9/11, the geopolitical currents that Washington had spent half a century mastering shifted all at once.

The deep currents would shift and slide, leave little ripples on the surface and eddies around the sides.

As the approach of day stirred the air, currents of putrefaction shifted back and forth across the Mithil.

Waves and currents shift the sand, continually building and eroding the shoreline.

During otherwise fine fishing weather, coastal currents would suddenly shift in their flow from a southerly direction to a northerly one.

While she could sense the future, the currents of choice and consequence constantly shifted, making it more difficult to determine where all the disparate threads would lead.

Tides and currents are constantly shifting the shoals.

"The currents of history are shifting in directions that will make us all more secure," she said.