Задать специальный вопрос, начиная с данного вопросительного слова :
who
what
when
where
why
whose
how
how many
how much
whom

ответ:

who is she?

what do you have?

when did it happened ?

where do you go ?

why didn't you come to school?

whose pencil is it?

how often do you go to the bazaar?

how many pencils do you have?

how much bread on the table?

whom will you give these gifts?