Linguistic units tend to form a hierarchy of extent.

The vacancy rates are high at 30% and these units tend to remain vacant for lengthy periods which give the area a "run down" feel.

Such units tend to operate in small groups, or sections, and so avoid direct enemy contact when ever possible.

The confusion is made worse when some units tend to officially adopt their nicknames.

Such large units tended to be more effective than smaller ones, for reasons that are easy to explain.

The units tend to come apart and reassemble into fibrils.

These units tended to be unreliable, and aren't common anymore.

The various units tend to work in isolation.

These units tend to cost $150 or more.

Existing low-cost units tend to be older than the housing stock in general.