Nam and Ba/ eat ice cream.
Nam and Ba aren't eating ice cream
Duong and Hung/ play badminton.
Duong and Hung aren't playing badninton.
Lan and Trang/ take photos.
Lan and Trang are taking photos.
Ha/ write a letter.
Ha is writing a letter.
Phong/ drawing a picture.
Phong isn't drawing a picture.