4. put the verb into the correct form. 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 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) ssau (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.
b) didn't come, didn't feel, will give
c) have jast finish, have been working
d) was ringing, was playing, was, got
e) will finish
f) have been coopereting
g) is happening,
i) don't know, has broken down
j) has invented
k) bought, haven't read
l) has never used, don't know