The program will run for 36 to 48 months on a trial basis.

Some customers have been using the service on a trial basis since early March.

In September 2008 the plant was put into operation on a trial basis.

The new hours are on a trial basis, a spokesman said.

Many are already working on a trial basis, and each will do a little good.

All this would be done on a three-year trial basis.

In December 2011, the system went into operation on a trial basis.

The policies have been in effect on a trial basis for the last two weekends.

We are planning to buy a business in Florida, and want to move there on a trial basis for a year or two.

He even agreed to work for two or three songs on a trial basis.