`4`/ They didn't eat noodles two hours ago. / Did they eat noodles two hours ago ?
`5`/ We always didn't have a nice time on Christmas holiday in the past / Did we always have a nice time on Christmas holiday in the past ?
`6`/ My father didn't decorated the Christmas tree. / Did my father decorate the Christmas tree?
Công thức thì past simple ( Dấu hiệu: yesterday, in the past, last week/month/year,...)
S + didn't + v infinite + O
? ) Did + S + v infinite + O
