What would you do if a terrible hearth-quake beat the city while you're in cl?

Yes, a hearth is a brick- or stone-lined fireplace or oven used for cooking and/or heating (especially in historical times but still used today). An "earthquake" would likely not bother me as I have indeed survived them although not in the magnitude of those happening in the Pacific this past week or so. For the most part, areas subject to earthquakes train their people and have drills on what to do. Best thing is to not panic and follow the instruction of the teacher or whomever is in charge. If it is so severe and no time to react, then if possible get under the desk to protect from anything falling and if possible, get to your designated Safety Shelter. Hope that eases your anxiety if you have any about earthquakes.