I can only hope he is given the time to make a substantial improvement.

That would be a substantial improvement over the 2.2 percent growth in 1986.

This means that the area the line is over needs substantial improvements.

Most of the more substantial planned improvements, however, have yet to be made.

There have been substantial improvements in freedom of movement within the country.

Each school, he said, made substantial improvements in test scores last spring.

Since then, he said, "There was no substantial improvement in our relationship."

There was substantial improvement in rural health care during the 1960s and 1970s.

In that year he carried out substantial improvements to the house.

This was a substantial improvement over the earlier mark, although the basic design still had not reached its potential.