About Unity2019.2.0 ECS

I used The ECS of Unity2018.2. I upgrade to Unity2019.2.0.
where is position component?
where is rotation component?
where is scale component?
where is RenderMesh component?
Only "xxx Proxy"
I use ConvertToEntity.cs，and Select 'Convert and destroy'. GameObject is destroy. But GameObject is visible in ECSDemo.

In ECS, How to use Unity2019.2.0？it is not esay than Unity2018.2.