Active Voice : - In the active voice, the sentence's subject performs the action on the action's target.

Passive Voice : - In the passive voice, the target of the action is the main focus, and the verb acts upon the subject.

Conversion  of Passive Voice Sentence into Active Voice For Simple Present Tense:

Rule used to identify that the sentence is in Passive Form with simple present tense is:

subject + is/am/are + third form of verb + object.

For Example : 

• A story is written by her. (passive)   

Here,'A story' is subject ,object is 'her' and 'written' is the third form of verb write.' A story' is singular subject so helping verb 'is' used here.'by' is used according  to the format of rule.

While converting into Active Voice the rule will be :

subject + will/shall + First Form of verb  + object.

In the question : -

The flowers are watered by the gardener every evening.

The active form of above sentence in simple present tense is : -

The gardener waters the flowers every evening. In this sentence , object (the flowers) is converted into subject( the gardener) and then ,  we use first form of verb (waters) and then the remaining part is the object (the flowers).

Thus , the Correct Option is C , which is The gardener waters the flowers every evening.

Active Voice : - In the active voice, the sentence's subject performs the action on the action's target.

Passive Voice : - In the passive voice, the target of the action is the main focus, and the verb acts upon the subject.

Conversion  of Passive Voice Sentence into Active Voice For Simple Present Tense:

Rule used to identify that the sentence is in Passive Form with simple present tense is:

subject + is/am/are + third form of verb + object.

For Example : 

• A story is written by her. (passive)   

Here,'A story' is subject ,object is 'her' and 'written' is the third form of verb write.' A story' is singular subject so helping verb 'is' used here.'by' is used according  to the format of rule.

While converting into Active Voice the rule will be :

subject + First Form of verb  + object.

In the question : -

1. Patients are treated by doctors.

The active form of above sentence in simple present tense is : -

Doctors treat patients. In this sentence , object (patients) is converted into subject ( doctors) and then ,  we use first form of verb (treat) and then the remaining part is the object (patients).

2. Students are taught by teachers.

The active form of above sentence in simple present tense is : -

Teachers teach students.  In this sentence , object (students) is converted into subject ( teachers) and then ,  we use first form of verb (teach) and then the remaining part is the object (students).

Thus , the Correct Option is D , which is 1. Doctors treat patients. 2. Teachers teach students.

Active Voice : - In the active voice, the sentence's subject performs the action on the action's target.

Passive Voice : - In the passive voice, the target of the action is the main focus, and the verb acts upon the subject.

Conversion  of Passive Voice Sentence into Active Voice For Simple Present Tense:

Rule used to identify that the sentence is in Passive Form with simple present tense  for interrogative sentence :

Is/are+object+past participle(V3)+by+subject

Example : - Is a book written by her ?

Here , the sentence is in interrogative form , so , in passive form we always start with verb Is , then we use object , then third form of verb which is written here , then use by preposition , then the subject which is her according to the rule .

While converting into Active Voice the rule will be :

Do/does+subject+verb+object

In the question : -

Is the gate entered by Tim Berners-Lee?

The active form of above sentence in simple present tense is : -

Does Tim Berners- Lee enter the gate? In this sentence , first we use helping verb which is does here , then we use subject ( Tim berners - lee) and then the object which is (gate here) .

Thus , the Correct Option is B , which is Does Tim Berners- Lee enter the gate? .