Future Perfect continuous....
In Future perfect continuous tense continuous or on going actions are expressed that will continuous in Future.
There will be time reference e.g. since 1847 or for two hours etc.
Use of "since"....
Since will be used when only starting time of an action is given and no ending time is known.
e.g since 1999, since morning, since evening etc.
This concept will be explain more clearly in further examples.
Use of "for"....
For will be used when total time of an action is given with ending time is known.
e.g for two hours, for six days, for one year etc.
This concept will be explain more clearly in further examples.
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Passive Sentences...
Structure...
Object + helping verb + First form of Verb( with "ing" ) + object + time reference.
In these sentences "will have been/shall ahve been" is used as helping verb.
First form of verb with "ing" .
Time reference is necessary for Future perfect continuous tense because if we do not use time reference it will simple present continuous tense.
Example...
- Sara will have been going to school since 2012.
Here we used...
"Since" because "2012" is starting time.
- Sara will have been going to school for five years.
- Here we used "for" because " five years" is complete time.
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Negative Sentences...
Structure...
Object +will not have been + First form of Verb( with "ing" ) + object + time reference.
In these sentences "will not have been" is used as helping verb.
First form of verb with "ing" .
Example...
- Sara will not have been going to school since 2012.
Here we used...
"will not have been" to make the sentence negative.
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Interrogative Sentences...
Structure...
Will + Object +have been + First form of Verb( with "ing" ) + object + time reference?
In these sentences ...
First form of verb with "ing" .
Question mark (?) at the end.
Example...
- Will Sara have been going to school since 2012?
Here we used...
"will " at the start of sentence to make the sentence interrogative.
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Some more examples...
- We shall have been doing our work for three months.
We shall not have been doing our work for three months.
Shall we have been doing our work for three months?
- Sara and Ali will have been writing a story since morning.
Sara and Ali will not have been writing a story since morning.
Will Sara and Ali have been writing a story since morning?
- You will have been teaching since 1994.
You will not have been teaching since 1994.
Will you have been teaching since 1994?
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