Помогите пожалуйста, здесь нужно поставить глагол в правильную форму a) Usually we ______

Помогите пожалуйста, здесь нужно поставить глагол в правильную форму a) Usually we _______________ (to have) classes on the campus, but today we ________________ (to go) to the training airfield. b) I ________________ (not to come) to the lecture yesterday. I ________________ (not to feel) very well. I hope my friends ________________ (to give) me the notes later. c) Specialists from our Research Institute _______________ (just to finish) the experiment. They ________________ (to work) on it for a month. d) My telephone _______________ (to ring) while I ______________ (to play) basketball in the sports center. It _______________ (to be) my friend Julie who told me I _______________ (to get) an excellent mark for my presentation. e) I want to go to this concert tomorrow. I think that I _______________ (to finish) writing my course paper. f) Samara University _______________ (to cooperate) with Oxford Polytechnic for 10 years by the end of this semester. g) I _______________ (not to read) the book on history of aviation yet, so I _______________ (do) it all day tomorrow. h) – What is that noise? What _______________ (to happen)? - I ________________ (not to know). Maybe the machine _______________ (to break down). j) Do you know who _______________ (to invent) this kind of engine? k) I _______________ (to buy) this book last week, but I _______________ (to read) it yet. l) Annie asked me how to use this machine. She _______________ (never to use) it before, so she _______________ (to know) what to do.