将下面一般过去时的句子转换为现在完成时
a.The meeting finished a moment ago. →
_【The meeting has finished for a moment .】
b.The film began 5 minutes ago. →
【The film has begun for 5 minutes. 】
c.They got to the airport an hour ago. →
【They have got to the airport for an hour】
d.He became a doctor 5 years ago. →
【He has become a doctor for 5 years. 】