You know what it means to turn a cat's eyes into a line? This may mean that the cat is focusing or preparing to do something. It may also indicate that the cat is thinking or being surprised.
Also, cats' eyes are very sensitive to light, and the pupil has a strong contraction ability. Under different light, the sphincter can adjust the pupil well to adapt to the light.
When the sunlight is average in the morning, the pupils become jujube-like; when the sun is strong at noon, the pupils shrink into a line; when the light is dim at night, the pupils become round and bright.
The phenomenon of cat vision deterioration
1. The crystals of its eyes become cloudy or gray.
2. It cannot be targeted when it jumps, for example, it may want to jump from the ground to the desk, but fall back to the ground without stepping right.
3. It wants to slap the toy but it always fails.