Complete the sentences with: in, out, off, up, on.
l) A lot of students signed ... for the new course, 2) They've just signed ... three new nurses and a doctor. 3) How do you usually sign ... when you write letters to your boyfriend? 4) Margaret signed ... and walked upstairs to the conference hall. 5) Could you hire a taxi for me while I'm signing ... 6) Thanks for answering my questions. l'm signing ... now. Bye! 7) I've signed ... to do some voluntary work next week. 8) OK. I'll sign ... We'll talk about it again at the beginning of the week. 9) If you sign ... for some organization you sign a contract. 10) Let's sign ... this girl as a secretary, she works on the computer very well.