Have you ever found that lots of kids love watching TV or playing video games? Is this good for them? 

Too much time in front of screens (屏幕) has made a difference to young children. They may develop important skills more slowly.

Researchers from the University of Calgary and the University of Waterloo in Canada studied about 2400 children. Their mothers reported how much time they spent looking at screens at ages 2, 3 and 5. The study showed children aged 2 had about 17 hours of screen time every week, 3-year-olds had 25 hours, and 5-year-olds had 11 hours.

According to the study, the reason for the decrease (降低) in screen time for 5-year-olds might be that children start school at around this age.

The mothers were also asked to answer questions about their children's development, such as how well they could do different tasks, or how well they could understand and answer questions. The study found that children who spent more time in front of screens when they were 2 years old were less probably to do well on developmental tests when they were 3 years old. And more screen time when children were 3 years old caused worse results when they were 5.

Dr Sheri Madigan explained that between the ages of 2 and 5, children's brains develop very quickly, and that what happens during this time can have long effects (影响).

Children may move less while they are watching screens, and may not talk with whoever is looking after them as much. They are not practicing and developing those important skills.