Вставьте нужные модальные глаголы (can, may, must)
... I take your pen?
... I invite nick to our house? Certainly, you ... .
They ... understand French.
You ... work hard at your English.
... I shut the door?

May/Can I take your pen?May I invite Nick to our house? Certainly, you can.Theycan understand French.You must work hard at your English.May I shut the door?