Passive sentence

1. Concepts

Passive sentences are sentences used when you want to emphasize the subject affected by an action rather than the action itself. According to each tense used, the structure of the passive sentence also changes.

2. Passive sentence structure

We have an active sentence structure of: S + V + O

Recipe passive voice common: S+ be + V3

Passive sentence structure In any tense form, divide tobe according to that tense, which you will learn below.

If a sentence has a verb and two objects, then to emphasize which object is which, we usually use that object as a passive subject. In general, the chosen object is an indirect object.

For example:

• I gave him a book = He was given a book (by me).

However, you need to note the following 2 points:

- If S - the subject in the active sentence is: they, people, everyone, someone, anyone, etc => then there is no need to put it in the passive sentence.

For example: 

• They stole my motorbike last night.

• My motorbike was stolen last night.

- If it is a person or object:

+ When directly causing an action, use 'by' to change to passive voice.

For example:  

• She is making a cake => A cake is being made by her.

+ To indirectly cause an action, use 'with'

For example:

• A door is opened with a key

3. Passive sentences in tenses

3.1. Passive sentences present tense

Then	Be proactive	Passive
Simple tense	S + V + O My mother often washes dishes.	S + be + V3 (+ by Sb/ O) Dishes are often washed by my mother.
Present continous	S + am/ is/ are + Ving + O She is making a cake.	S + am/ is/ are +  being + V3 (+ by Sb/ O) A cake is being made by her.
Present perfect	S + have/ has + V3 + O He has washed his car for hours.	S + have/ has + been + V3 (+ by Sb/ O) His car has been washed by him for hours.

3.2. Passive sentence past tense

Then	Be proactive	Passive
Simple past	S + V-ed + O My mother bought that washing machine in 2010.	S + was/ were + V3 (+ by Sb/ O) That washing machine was bought by my mother in 2010.
Pastcontinue	S + was/ were + Ving + O Yesterday morning she was cutting the grass.	S + was/ were +  being + V3 (+ by Sb/ O) The grass was being cut by her yesterday morning.
Simple past	S + had + V3 + O She had cooked lunch before leaving.	S + had + been + V3 (+ by Sb/ O) Lunch had been cooked by her before she left.

 
3.3. Passive sentences in the future

Then	Be proactive	Passive
Future simple	S + will V + O I will feed the dogs.	S + will be + V3 (+ by Sb/ O) The dogs will be fed.
Future Perfect	S + will have + V3 + O They will have completed the assignment by the end of January.	S + will have + been + V3 (+ by Sb/ O) The assignment will have been completed by the end of January.

 
4. Passive sentences use modal verbs

Particularly with modal verbs, the formula of the passive sentence is slightly different:

S + modal verb + be + V3 ( + by O )

For example:

• This must be done before Christmas.

Special form:

Need + Ving = Need to be + V3