Ex. 255, буду очень признательна

1) Hello! Where are you going(Pr.Cont.)? -- Nowhere in particular. I'm just taking(Pr.Cont.) a walk.

2) Our students have done(Pr.Perf.) all kinds of exercises and now they are(Pr.S.) sure that know(Pr.S.) this rule well. They hope(Pr.S.) they will make(F.S.) no mistakes in the paper.

3) The expedition has covered(Pr.Perf.) hundres of kilometres, but they are(Pr.S.) still far from their destination.

4) Are you going(Pr.C.) to Great Britain next year? // тут to be going to в смысле "собираться что-или сделать"

5) Yesterday Nick said(P.S.) that he had read(P.Perf.) so much during his summer holidays.

6) At the age of twenty my father combined(P.S.) work and study.

7) A great number of students were studying(P.Cont.) in the reading room when I entered(P.S.) it last night.

8) The storm was raging(P.Cont.) the whole night, and the sailors were trying(P.Cont.) to do their best to save the ship.

9) Mikes friends could hardly recognize him as he had greatly changed(P.Perf.) after his expedition to the Antarctic.

10) When I entered(P.S.) the hall, the students were listening(P.Cont.) to a very informative lecture on history of the English language.

11) I dont think she has ever read(Pr.Perf.) such a book.