Contrastive Conjunction and Modal Perfect

Contrastive Conjunction and Modal Perfect

Modals in the past form are used in the past time.They are could, would, should, and might. Formula of modals is:
Modals + verb 1 + O/C.
Can be used in every tenses.
a.    Could is the past tense of can
The modal auxiliary could is used.
To express an ability in the past:
 -  I could always beat you at tennis when we were kids.
To express past or future permission:
  - Could i bury my cat in your back yard?

Persuading and Encouraging, Preventing Someone From Doing Something

Expressions of persuading :

Are you really sure you can’t/couldn’t...?
Don’t be so silly!
I really think it would be a pity if we didn’t...

Are you quite sure you won’t consider...?

Passive Sentences

Passive voice verbs are used in writing much more often than in speech, and they are used in some types of writing much more often than in others. Passives are used more in journalism (newspapers, magazines) than in fiction (novels, stories), but most journalists and fiction writers use far more active than passive sentences. However, passives are very common in all types of scientific and technical writing. Scientific articles often contain more passive than active sentences. You should not use passive voice verbs unless you have a good reason.

Direct speech and Indirect speech

Direct speech refers to reproducing another person’s exact words or saying exactly what someone has said (sometimes called quoted speech)
Here what a person says appears within quotation marks ("...") and should be word for word.

For example:
She said, "Today's lesson is on presentations."
or
"Today's lesson is on presentations," she said.