DevEco Service预览器一直无法正常使用怎么回事？

 

 

连hello world 也运行不了。。。

preview log如下：

[Compile Result]  ArkTS:ERROR File: C:/Users/ASUS/DevEcoStudioProjects/MyApplication4/entry/src/main/ets/entryability/EntryAbility.ts:2:21
[Compile Result]  Cannot find module '@ohos.application.Ability' or its corresponding type declarations.
[Compile Result] Compile error occurred. Fix it based on the above message.