Keep the books carefully,----they will get torn
the play was interesting --- the dance presentation was boring.
she left early --she could reach school on time
he went for a walk--he was not feeling well

1.otherwise
2.but
3.so
4.because

1. Keep the books carefully otherwise they will get torn.
2.The play was interesting but the dance presentation was boring.
3.She left early so that she could reach school on time.
4. He went for a walk although he was not feeling well.

Hope you get an help..........
SHRUTI GOEL