Модальный глагол can. Правила построения утвердительных, отрицательных и вопросительных предложений.

Can – мочь, уметь
+ I/we/you/they/he/she/it can V. E.g. I can run. The boy can play tennis.
- I/we/you/they/he/she/it cannot (can’t) V. E.g. I can’t run. The boy can’t play tennis.
Yes/No question
Can I/we/you/they/he/she/it V? E.g. Can you run? Can the boy play tennis?
Short answers
Yes, I/we/you/they/he/she/it can. No, I/we/you/they/he/she/it can’t.
Special question
Why
What can I/we/you/they/he/she/it V?
Where
How
E.g. What games can you play? Where can the children play football?
Subject question (вопрос к подлежащему; ответ – само подлежащее)
Who can V? E.g. Who can play tennis? I can. Vitalik can.