Questionwhy it is dangerous to leave pets in the car?
AnswerThe biggest danger is suffocating because a closed car heats up very quickly in the sun even in fairly cool weather. They can also freeze in the winter. Some other problems are chewing things up or being stolen. Not only can their teeth destroy your upholstery, but they can choke on the pieces. If you must absolutely leave a pet in a car, keep it short and never on a warm day.
This may be a duplicate answer due to the technical problems on the site. If so sorry. Better to answer twice than not at all.