Resposta :
a) They are cooking dinner.
b) I am reading a magazine.
c) He is sleeping now.
d) She is riding a bike.
e) She is doing her homework.
Espero ter ajudado :)
a) They were cooking dinner.(cook)
b) I was reading a magazine.(read)
c) He was sleeping now.(sleep)
d) She was riding a bike.(ride)
e) She was doing her homework.(do)
A resposta da pessoa ali de cima que te respondeu está errada porque ela colocou as frase no PRESENTE continuo e o exercício está pedindo no PASSADO continuo, então o jeito certo de fazer é como eu fiz