Trả lời :
a.Tim and Lucas work at weekends.
⇒Tim and Lucas don't work at weekends.
b. I like classical music.
⇒I don't like classical music.
c.These exercises are difficult.
⇒These exercises aren't difficult.
d.She has sciences on Fridays.
⇒She doesn't have sciences on Fridays.
Giải thích :
×Câu a, b, d :
≡Don't : Dùng với chủ ngữ I , You , We, They
≡Doesn't : Dùng với chủ ngữ He , She , It
⇒S + don't/doesn't + V-inf
×Câu c :
≡Aren't = are not. Used when the subject is multiple items/plural.
⇒Ví dụ: They aren't students.