1.My sister ... an apple
to eat
is eating

2.Sttella and her sister ... their room
is tidying
to tidy

3.I ... with my dog
am playing
is playing
are playing

4.Lisa ... lunch in the canteen
is having
is haveing
are having

5.The boys ... to their teacher
are talking
is talking
to talk

6.Monica ... back to home
are walking
is walk
is walking

7.The dog ... at the man
is bark
is barking
are barking

8.The girls ....
are eating and skipping
is eat and skip
are to eat and skip

9.The policeman ... the old across the road
are helping
is help
is helping

10.The boys ... soccer in the field
is playing
are playing

11.The little cat ... under the tree
is sleeping
to sleep

12.Some boys ... hamburgers
is buying
to buying
are buying

13.She ... come back home to avoid the rain
is running
is runing