8月23日晚上19:06--19:44
The situation is serious. Something must be done before it's too late.
A mystery is something that can't be explained.
The music was very loud and could be heard from a long way away.
A new supermarket is going to be built next year.
Please go away. I want to be left alone.
完成时：
I haven't received the letter yet. It might have been sent to the wrong address.
If you hadn't left the car unlocked, it wouldn't have been stolen.
There were some problems at first but they seem to have been solved.
现在完成时：
Have you heard the news? The President has been shot !
Have you ever been bitten by a dog?
'Are you going to the party?' 'No, I haven't been invited.'
过去完成时：
The vegetables didn't taste very good. They had been cooked for too long.
The car was three years old but hadn't been used very much.
现在进行时：
There's somebody walking behind us. I think we are being followed.
'Can I help you, madam?' 'No, thank you. I'm being served.'
过去进行时：
There was somebody walking behind us. We were being followed.
练习题
If something is unbreakable, it can't be broken.
If something is edible, it can be eaten.
If something is unusable, it can't be used.
If something is invisible, it can't be seen.
If something is portable, it can be carried.
A decision will not be made until the next meeting.
I told the hotel receptionist that I wanted to be woken up at 6:30 the next morning.
Do you think that less money should be spent on armaments?(武器，装备)
This road is in very bad condition. It should have been repaired a long time ago.
The injured man couldn't walk and had to be carried.
It's not certain how the fire started but it might have been caused by an electrical fault.
They have postponed the concert. The concert has been postponed.
The computer is being used by somebody at the moment.
I didn't realize that our conversation was being recorded.
When we got to the stadium, we found that the game had been cancelled.
A new ring road is being built round the city.
A new hospital has been built near the airport.
It has been stolen.
Somebody has taken my umbrella.
He has been promoted.
It is being redecorated at the moment.
It is working again. It has been repaired.
Two people were arrested last night.
It was blown down in the storm. It had been blown down in the storm.
Nobody has seen him since then.
Have you ever been mugged?
