11. Where your sister (to be) now? - She (to be) in her room. She (to do) her homework.

11. Where **is** your sister now? - She **is** in her room. She **is doing** her homework.

* **Where is your sister now?** (Где твоя сестра сейчас?) - Present Simple, вопрос о текущем местоположении.
* **She is in her room.** (Она в своей комнате.) - Present Simple, констатация факта о текущем местоположении.
* **She is doing her homework.** (Она делает домашнее задание.) - Present Continuous, действие происходит в данный момент.