Choose the correct preposition to coplete the sentences.
1.Do not forget to check (at/in) two hours before your flight.
2.if you do not throw these scrissors(away/up), you will be in trouble with the security check.
3.We'll have to get rid (of/off) these old newspapers.Nobody needs them.
4.Hurry up! Your flight is (on/in) time .
5.I like to sit (by/in) the windiw , but i got a place (by/in) the aisle