24. They said that they had to do the assignments then.

12."They are supposed to be landing at London airport ".I said
--> I say that they have to land at London airport
19.Nam said :"My uncle often plants the vegatables in the afternoon"
-->Nam said that his uncle often grow vegetables in the afternoon
23.Lan's mother said :"My daughter usually brush her teeth before meals
-->Lan'mother said that Lan often brushing his teeth before meals
24.They said :"We have to do the assign ments now"
-->They say now they have to do ments
25.Lan says :"My sister seldom rides a bike to school"
-->Lan said that his sister rarely go to school