1. Able , Capable :
He is an able man .
here able is used to convey a general impression.
He is capable of uttering falsehood.
The word capable is used to denote something particular.
2. Abstain , Refrain
I abstained from meat.
refers to a thing
I refrained from fighting.
refers to an action
3. Adapt , Adopt
We must adapt ourselves to circumstances.
We must adopt a definite course of action.
4. Adjacent , Adjoining
The adjacent countries were friendly.
means “in close proximity“
The adjoining house is for sale.
5. Admission , Admittance
Admission is difficult .
refers to being admitted to a class or society.
We prayed for admittance to the King’s presence.
refers to being admitted usually to a place.
6. Alternate , Alternative
He and I do the work on alternate days.
refers to leaving one (day) in between.
There is no alternative for us but to die.
refers to the other course.
7. Alternation , Alternative
Owing to the rotation of the earth, we have alternation of day and night .
means successive change.
There is no alternative but to submit patiently to the ill-treatment.
means another course.
8. Ancient , Antiquated
India is an ancient country.
means old in time.
The Moyas are an antiquated people.
means old in fashion.
9. Artist , Artisan
The painter is an artist.
denotes some fine art.
The carpenter is an artisan.
denotes mere handicraft.
10. Artist , Artiste
Ravivarma was a great artist.
means an expert in a fine art.
Cine artistes are now honoured by government .
an actor by profession.
11. Assent , Consent
The President has given his assent to the Bill.
My father has given his consent to my marriage.
12. Astonished , Surprised
I was astonished at the feat.
amazed , filled with wonder
I was surprised at his coming .
made to feel something unexpected
13. Avenge , Revenge
I avenged the murder of my friend.
An act of justice , rough and common.
I revenged myself on my neighour.
An act of personal satisfaction. “revenged” is almost always followed by a reflexive pronoun as an object.