• for example:- The train left at 8 o’clock.

• She used to go to temple at Dussehra and Diwali.

• He came here at the weekend.

• She married at the age of twenty.

• We rested at noon/dawn/dusk.

• for example:- She was born in 2007.

• English literature flourished in the 16th century.

• The theft took place in the day-time.

• They visited this place in summer.

• He called on me in the evening.

• It all happened in three minuets/hours/days/years. etc. 

• for example:- He was born on October 5,2012.

• We went to see a movie on Tuesday.

• We congratulated him on his birthday. 

• We gave them a gift on their 25th marriage anniversary.

NOTE :- We use ‘on’ with ‘morning’, ‘afternoon’, ‘evening’, etc.  when they are modified: 

• for example:- People did not come out of their houses on a night like this.

• We went for fishing on a pleasant morning.

• They reached here on a hot afternoon

• for example:- We work during the day and sleep during the night.

• During the war many people were killed.

• We try to contact people during October.

• During the journey I came to respect her.

• She used to ring up many times during the week.

• for example:- You must come to me by 8 a.m.

• He will finish this work by 5 o’clock.

• By that time, the sun was up.

• Applications must be recived by 10th April.

By can be used instead of during with almost the same.
for example:- We took rest by day and travelled by night.
By mid afternoon about 5,000 people had visited the exhibition.

In:- In is used to indicate the period of time in which something happens. We use ‘in’ with centuries, years, seasons, months, periods of the day ‘morning’, ‘evening’, ‘afternoon’,etc.

During :- During may be used instead of ‘in’ with periods of the day, months, seasons, years, decades and centuries to express the idea that something continues throughout the whole of a specidied period.

By :- By is used to indicate the latest time at which an action will be finished.