A)Is Kate writing a letter to her friend at home now?
B)Is Kate writing a letter to her friend or to her grandmother at home now?
C)What is Kate doing At home now?
Where is Kate writing a letter to her friend now?
When is Kate writing a letter to her friend at home?
Who is writing a letter to her friend at home now?
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Не могу понять,причем вопросы How?Why?,ведь в предложении не сказано ПОЧЕМУ? она пишет письмо другу и КАК? она ему пишет.
Если бы было предложение,например:
Kate is witing a letter to her friend quickly,тогда бы было Как?-быстро.