Sentence examples for systems have existed from inspiring English sources

Modern rapid transit systems have existed since the 19th century.

Such systems have existed in some form for about a decade.

Gas and water systems have existed since the 1860s and electrical and sewerage systems since the early 20th century.

(Systems have existed since the 15th century, but Labanotation and Benesh notation, developed in Britain in the 1950s, are the two types most used today).

Although systems that remove salt from saltwater, or desalination systems, have existed for decades, they are typically large-scale installations that require lots of energy to operate.

While for decades several such systems have existed in the Pacific (i.e in Hawaii, Alaska and Japan), there was no way to warn the people along the coast of the Indian Ocean when the biggest earthquake in forty years struck the area in December 2004.

Before the introduction of the zloty, many currency systems had existed in Poland.

A scientific understanding of living systems has existed since the second half of the 19th century.

In the 16th century some students of the law and customs of the fief declared that feudal institutions were universal and maintained that feudal systems had existed in Rome, Persia, and Judaea.

Third and Fourth streets, as part of the Coronado street system, have existed since the 19th century, and were paved in the early 20th century.

The system has existed for three decades, ever since the state began emptying its psychiatric wards.