SARS deaths are usually caused by lung damage.
"Derailments are usually caused by equipment failures," Bibel wrote.
Colds are usually caused by viruses, and antibiotics don't kill viruses.
Vaginal and vulvar cancers are usually caused by the human papillomavirus, which also causes cervical cancer.
Such accidents are usually caused by a failure to ventilate methane gas from the shaft.
Infections of the prostate are common and are usually caused by bacteria that inhabit the stool.
Bruises are usually caused by a blow or pressure but, in aged persons, may occur spontaneously.
Such cases are usually caused by a condition known as cholesteatoma of the middle ear.
Mr. Tanen reassures him that he is familiar with such cracks, which are usually caused by dry air.
Swarms are usually caused by the emergence of a new queen and the overcrowding of an existing hive.
Ukraine's frequent coal mine accidents are usually caused by methane, a naturally occurring gas that is colorless, odorless and highly explosive.
