Замените существительные личными местоимениями.
1.The teacher helped the pupils to translate the text.
2.Mother asked Mary to wash the plates.
3.My friend writes a letter to her sister.
4.Jane took three books from Jim.
5.His cousins live in Moscow.
6.Their grandmother and grandfather will come tomorrow.
7.Mary work in a shop.

Если нужно поменять ВСЕ существительные, то будет так: 1) He helped them to translate it.2)She asked her to wash them.3)She writes it to her.4)She took them from him.5) They live in Moscow.6)They will come tomorrow.7)She works in it.