Incorrect His room's windows are open.
Correct The windows of his room are open.
Incorrect It is everybody's duty to defend their country.
Correct It is everybody's duty to defend his/her country.
Incorrect Either of them are to go.
Correct Either of them is to go.
Incorrect More police was sent to the scene of the crime.
Correct More police were sent to the scene of the crime.
Note : The noun police is singular in form but plural in sense.
Incorrect Mary pretended to not recognize me.
Correct Mary pretended not to recognize me.
Incorrect She neither speaks English nor Bangla.
Correct She speaks neither English nor Bangla.
Incorrect Only I and my friend were at the concert.
Correct Only my friend and I were at the concert.
Incorrect There is a dirty mark on the rug which must be removed.
Correct On the rug, there is a dirty mark which must be removed.
Incorrect Lizzie approached me and held my hand, said, "Hello !"
Correct Lizzie approached me, held my hand, and said, "Hello !"
Incorrect The climate of Japan is different from Taiwan.
Correct The climate of Japan is different from that of Taiwan.
Incorrect We realized where our weak points were and how to get rid of them.
Correct We realized where our weak points were and how we could get rid of them.
Incorrect All I know is my friend is right.
Correct All I know is that my friend is right.
Note : When the "that clause" is the object of a verb, the subordinating conjunction that may be omitted. When it is a complement of the verb be, that cannot be omitted.
Incorrect Most of us found difficult to comprehend his speech.
Correct Most of us found it difficult to comprehend his speech.
Incorrect Her heart sank and could hardly stand.
Correct Her heart sank and she could hardly stand.
Note : Not changing the subject will make "her heart" seem to have "feet" on which it stands.
Incorrect While doing the work, there are obstacles ahead.
Correct While doing the work, they met with obstacles.
Note : A certain action must be attached to the actor; otherwise the action becomes dangling.
Incorrect Mandy is easy to suffer from cold.
Correct Mandy suffers from cold easily.
Incorrect How much is the price of this pen ?
Correct How much is this pen ? Or How much does this pen cost ? Or What is the price of this pen ?
