英语日常口语 Unit18.doc

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英语日常口语 Unit18

英语日常口语 Unit18:Emergency
本单元是关于紧急情况的对话
Alice: Oh it's so quiet tonight! You coe Use
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We use the present perfect to talk about something that happened before now but we don't say exactly when it happened.
Alice says, 'She has gone for a break'. The doctor isn't in the room now because she left the room for her break some time before now.
The father says, 'He's stopped breathing'. The patient isn't breathing now because he stopped breathing at some unknown time in the past.
If we refer to the time when the doctor left the room or when the patient stopped breathing, then we use the past simple.
She went for her break at midnight.
He stopped breathing 1 minute ago.
The present perfect has two parts the main verb and the auxiliary verb.
The formthe main verb
He has stopped breathing.
She has gone for her break.
In these examples, the main verbs are 'to stop' and 'to go'. We use the past participle of the main verb. Some verbs are regularyou add 'ed' to the infinitive without 'to', while others are irregular. You have to learn the past participle .
to go gone to take taken to find found
to see seen to give given to buy – bought
The form – the auxiliary verb
The auxiliary verb is 'to have'. When we make the present perfect we use the present simple form of 'to have':
I/you/we/they have ...
he/she/it has