A preposition connects a noun (with or without an article) or a pronoun to some other word. Prepositions are the “little words of English”.
In is used with the names or countries and large towns; at is used when speaking of small towns and villages.
In and at are used in speaking of things at rest; to and into are used in speaking of things in motion.
On is often used in speaking of things at rest; and upon for the things in motion.
Till is used of time and to is used for place.
With often denotes the instrument and by the agent.
Since is used before a noun or phrase denoting some point of time and is preceded by a verb in the perfect tense.
From is also used before a noun or phrase denoting some point of time but is used with non-perfect tense.
For is used with a period of time.
Use of in before a period of time means at the end of period, but use of within before a period of time means before the end of period.
Scarcely should be followed by when and not by but.
For example: Scarcely had he gone, when (not than) a policeman knocked at the door.
The phrase ‘seldom or ever’ is wrong ‘Seldom or never’ is right.
For example: Such goods are made for export, and are seldom or never used in this country.
Examine the following sentence:
Beside means at the side of while besides means in addition to.
Above and Below merely denote position While over and under also carry a sense of covering or movement.
Here over is used to denote upward position and movement also.
During is used when reference is made to the time within which something happens. For is used when we are talking about how long something lasts.
Compare is followed by to when it shows that two things are alike. It is followed by with when we look at the ways in which two things are like and unlike each other.