1.grandmother does not water flowers for half an hour
2.kitten does not run ten minutes in the garden
3.Nancy hasn't helped her mother since childhood
4.students did not write the dictation for 25 minutes
5.the weather is changing fast
6.workers don't build the stadium for a year
7.We didn't have been taking part in the sports competitions since the primary school.
8.girls have not picked apples since 6 in the morning
