Why objects exist but events occur

I distinguish between sentences like Sentence (2) has the subinterval property. If it is true at an interval t it is true at every subinterval of t. (1) lacks this property. (1) reports an event. (2) reports a state. Events do not have the subinterval property but states do have it, and so do objects. If something is a linguist at an interval t then that person is a linguist at all subintervals of t. I argue that ‘exists’ applies to things which have the subdinterval property, and ‘occurs’ applies to things which lack it.