The phrase "are properly used" is correct and usable in written English.
It can be used when discussing the appropriate or correct application of something, such as rules, tools, or methods.
Example: "The guidelines provided in the manual ensure that the tools are properly used to achieve the best results."
Alternatives: "are utilized correctly" or "are employed appropriately".
Antibiotics are often prescribed for illnesses against which they are ineffective, the authors say, but even when they are properly used, the elderly and frail can be particularly susceptible to their side effects.
UN monitors do oversee the distribution of food and medicine and check that spare parts for the oil industry are properly used, but Iraq shows no sign being willing to readmit weapons inspectors.
The latest measures follow a Labour announcement on Saturday that in government it would tackle a shortage of childcare places by doubling the number available at Sure Start – adding at least 50,000 more places – and ensure children's centres are properly used rather than being mothballed.
Time domain integral operators are properly used in the synthesis of the proposed parametric estimation approach.
Experiments are most useful when investigating predictions derived from explicit theories, and it is theories, rather than experimental results, that are properly used to explain features of natural settings.
The research result can serve as a guideline for the key parties in mobile marketing industry to facilitate the development of the industry and ensure that advertising resources are properly used.
Among other things, the SEC plans to look at whether privately-traded tech firms are properly using a loophole in the law to bypass public disclosure rules.
The burning debate is whether the mega and Super Mega churches are properly using their power and prestige for the good of their community, or abusing that power and prestige for selfish, personal gains.
Make sure you are properly using exercise equipment in order to prevent injuries.
Are maps being properly used by American military planners?
"Like" is properly used as a preposition.
