A more thorough analysis of the gap also points to the essential link between teacher quality and student success.

Thus, for many, the Q-10 is an essential mass-transit link.

And although stylistically very different from one another, they share some essential links.

These organisms are often essential links in the food chain between primary producers and larger species.

If they are right, Japan will control another essential link in the food chain of high technology.

The Tippit murder provided the essential link to the assassination.

The budget provides the essential link between the important elements of programming and operation.

It represents an essential link between process research and commercial production.

By 1972, The Times was being seen as an essential link to civilization itself.

Why break the essential link between sales and after-sales service?