As a result, many occupational barriers have fallen over the last 10 years.

Even as I write, the last major barrier is finally falling.

Once these barriers fell, the middle class rushed in to stay.

But the tall social barriers here are falling - at least between old money and new.

But the barriers that keep us here in the known Cosmos must fall.

But you can bet that such barriers will soon fall.

But barriers have fallen, and new discoveries are being made.

It was however important that the barrier could rise and fall with the level of water in the canal.

But over the course of the 90's, according to surgeons I spoke with, many barriers fell.

This is, in many ways, good news, because it means that some barriers to opportunity have fallen.