вместо точек вставьте соответствующие притяжательные местоимения-прилагательные или местоимения-существительные. Tell him not to forget ... ticket; she mustn't forget ... either. Whole books are those? Are they ... or ... I see that he has lost ... pencil ; perhaps you can lend him ... Lend them ... dictionary; they have left ... at home. My trunk is heavier than ... We've taken ... dictionaries; has she taken book, it must be ...

Tell him not to forget  his ticket; she mustn't forget hers either.

Whose books are those? Are they yours or theirs? 

I see that he has lost his pencil; perhaps you can lend him yours.

Lend them  your dictionary; they have left theirs at home.

My trunk is heavier than his/yours.

We've taken our dictionaries; has she taken a book, it must be hers.