please ! Can anybody correct this sentence?

[Noor92]

The question: how can I rewrite these sentence in the present perfect passive ?​

1- How long have we used computers ?​

I couldnt rewrite the sentence ..!!​

2- The researchers have discovered many new herbs since World War 1 .​

My answer: Many new herbs have been discovered since Wold War 1.​

3- Housemaid has cleaned the dressing trolleys with the antiseptic .​

My answer: The dressing trolleys with the antiseptic have been cleaned.​

4- The doctor has prescribed a medicine for the patient in bed 6.​

My answer: A medicine for the patient in bed 6 has been prescribed .​

5- The researchers have found sucrose in the stalk of many plants.​

My answer: A sucrose in the stalk of many plants has been found .​

6- Ms.Sara has published two books on study skills.​

My answer: Two books on study skills have been published .​

Finally , If you can explain to me how to rewrite .. or the rules that we have to follow .. to get the right structure of any sentence we rewrite?​

Because I have a problem with this grammer topic when i change the structures... please help me !!!!​

 

[Verona_82]

Hi.
Please note I'm not a teacher.

The question: how can I rewrite these sentence in the present perfect passive ?​

1- How long have we used computers ?​

I couldnt rewrite the sentence ..!!​

Finally , If you can explain to me how to rewrite .. or the rules that we have to follow .. to get the right structure of any sentence we rewrite?​

Because I have a problem with this grammer topic when i change the structures... please help me !!!!​

I suggest writing "How long have computers been used?"

I think 'housemaid' in 3 needs an article, and I'd use 'the'. In addition, I'd rewrite your sentence as "The dressing trolleys have been cleaned with the antiseptic".
It seems to me that 'sucrose' is an uncountable noun; I suggest you not use 'a' in your answer in 5.

 

[Rover_KE]

Noor, all your answers fail to include the subject of the verb in the active sentences.

Example: 'Dad paid the bill' >> 'The bill was paid by dad'.

Try again.

Rover

 

[Noor92]

Thank you very much .

For number 5 .. I forgot this rule ... .. I am really sorry :-D

Thank you again , and for your help .

I got many benefits from your reply .

 

[Noor92]

Noor, all your answers fail to include the subject of the verb in the active sentences.

Example: 'Dad paid the bill' >> 'The bill was paid by dad'.

Try again.

Rover

.. :-D

I understood your reply . But I dont have any problem with the short sentences(actually, I mean with the short object). What I was want to say that I have a problem when the object involves more than one word. So, I need to solve my problem !!:-(