Uzupełnij zdania "in", "on" lub "at".

1) I am keen .......... biology.
2) Please, come .......... Tuesday.
3) We never go away .......... August.
4) Do you like skiing ............ winter?
5) My sister is standing ......... the queue to the shop.
6) John sits ......... his desk all day long!
7) Here we are ......... last
8) He buys a newspaper ......... the way to the station.
9) Then he reads it .......... the train.
10) Let’s put this box ............. the corner of the room.
11) He listens to the radio .............. the evening.
12) Why are you looking ........... me in such a strange way?
13) Mary is interested ............ chemistry.
14) Bob is trying to concentrate .............. his work.
15) It depends ........... you only.
16) I often watch interesting programmes .......... TV.
17) She never stays ........... home alone.
18) Put ......... your coat! It’s cold.
19) Somebody is knocking .......... the door.
20) He gets up ......... 6 o’clock every day.