How does the eye always feel to have foreign body to return a responsibility

The eyes show obvious foreign body sensation, often seen in the following reasons: first, conjunctivitis, when the body immunity drops, pathogens easily invade the conjunctiva, resulting in acute conjunctivitis, eyelid conjunctiva shows a large number of proliferation of follicles, so patients will feel that the eyes show obvious foreign body sensation. Third, eyelid trichiasis, when the eyelashes of the eyelids are abnormally chaotic and backward to the eyeball surface, when the eyes blink, trichiasis has been stimulating the eyeball, so it shows obvious foreign body sensation.