He has designed more than 30 types of safety equipments, including a low cost earthquake alarm, an epicenter direction finder and an epicenter distance locator.是什么意思_He has designed more than 30 types of safety equipments, including a low cost earthquake alarm, an epicenter direction finder and an epicenter distance locator.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句