‘Before’ and ‘By’ are two independent terms related to English grammar which are often confused with each other when used as prepositions concerning time. In English, ‘Before’ is used as an adverb, a conjunction and a preposition. It refers to a time that is in advance of a particular time or event. For example, She has to submit her homework before Friday.
The meaning inherent in this sentence is that the homework must be submitted by Thursday at the latest.
‘By’ on the other hand is used as a preposition and an adverb. Regarding time, it is used to allude to a time that is not later than a given deadline. For example, She has to submit her homework by Friday. The inherent meaning of this sentence is that the homework must be submitted on Friday before midnight.
By vs Before
The difference between By and Before is that the former is used to refer to a task that must be completed ‘before or on’ time. While the latter refers to a task that must be completed ‘earlier’ than the given deadline.
Comparison Table Between By and Before (in Tabular Form)
|Parameter of Comparison||By||Before|
|Usage in Grammar||It is used as a preposition or an adverb.||It is used as an adverb, a conjunction and a preposition.|
|Implications||I. Implies the end of a particular time.|
II. Refers to the particular location of an object adjacent to a place or another object.
|I. Refers to a period that is in advance of a particular event or time.|
II. Implies a location that is in front of something.
|As a temporal word||It refers to a time that is ‘either before or at the last moment’ of the given deadline.||It stands for a period that is ‘earlier than a given time or a deadline’.|
|How to use||‘By’ is mainly followed by a named time, say 10 o’clock or days of a week, say Monday, Tuesday, etc. or simply ‘the time’.||‘Before’ is mostly followed by phrases like ‘before breakfast’, ‘before you go to sleep’. However, it may be also followed by the mention of a specific time or a day of the week.|
|Alternative phrase||No later than and by close of||Prior to, in advance of and ahead of|
When to Use By?
In sentence construction, it can be used as a preposition or an adverb.
As a preposition, it serves a variety of purposes:
- Indicate a subject or a medium performing a function. In this case, there are three ways in which ‘By’ can be used:
- Following a passive verb, e.g. the job was done by him.
- Following a noun implying an activity, e.g. The Taj Mahal was the result of years of hard work by the labourers.
- Recognizing the author of a book or text, e.g. a novel by Jane Austin.
- Identifying the means to achieving an end. For example:
- We travelled there by bus.
- Tea is made by adding tea and sugar in boiled water.
- Implying a quantity or a measurement or certain parameters. For example:
- She was shorter than her brother by a few centimeters.
- She divided it by 9.
- Implying a period that is in advance or at the last moment of a given deadline. For example:
- She must submit her article by Wednesday.
- By the time he reached the station, the train was gone.
- In reference to the physical location of a person or an object that is adjacent to or beside another object or person. For example:
- The dead body was found by her building.
- Alluvial soil is found by the river Ganga.
- Related to or according to something or someone. Example:
- Anything my father says is all right by me.
- He has done his job by her.
As an adverb, it is used to refer to go past or beyond something, e.g. she jogged by her teacher’s house.
‘By’ is also used as an alternative for the noun ‘Bye’.
When to Use Before?
In a sentence, ‘Before’ can be used as an adverb or a preposition or a conjunction. The term has been derived from the Germanic term ‘bevor’. As a temporal word, it can be used in three ways:
- A period of time that is in advance or prior to a particular event or time. For example:
- She has to complete the syllabus before the commencement of her exams.
- The train departed before she reached the station.
- Until or till the transpiring of a particular event, e.g. it was almost an hour before his father arrived.
- Implying an event of the past, e.g. though I have never seen her before, I still talked to her.
In the ibid cases, ‘Before’ may be used as a preposition, a conjunction or an adverb.
But as a preposition, ‘Before’ has another usage as well and that is spatial usage. In this case, the term is used to imply the physical location of someone or something that is in front of or ahead of another person or object. For example:
- She has to give her speech before a large audience.
- The Shopping Mall is just before the bus stop.
Apart from the above mentioned usages, the term is also used to indicate a preference, e.g.
For a soldier, duty towards the nation comes before everything else.
Main Differences Between By and Before
- In Grammar, both terms are used as preposition and adverb. But ‘Before’ is also used as conjunction while ‘By’ is not.
- The main difference between ‘By’ and ‘Before’ is that ‘By’ refers to a period of time that is supposed to be ‘before, until or at the endpoint of a particular time’. While ‘Before’ implies a time period that is ‘in advance or ahead of a particular time’.
- In a sentence, when ‘By’ is used with reference to time, it is mainly followed by a named time or any day of a week. For example: ‘11:00 pm’ or ‘Friday’. If a specific time or day is not mentioned then it may simply be followed by words like ‘the time’.
- On the other hand, when ‘Before’ is used with reference to time, it is followed by phrases like ‘before dinner’ or ‘before the football match’. However, it may also be followed by a named time or day of a week.
- Some of the alternative phrases for ‘By’ are ‘no later than’ and ‘by close of’. While for ‘Before’, it is ‘prior to’, ‘in advance of’ and ‘ahead of’.
- Other usages: With reference to a physical location, ‘By’ is used to refer to a person or an object that is beside or adjacent to another object or person. While ‘Before’ is used to allude to a person or an object that is in front of another object or place.
‘By’ and ‘before’ are some common temporal words that are used in English. But they are often confusions regarding their actual meaning as to what time do they refer to with relation to a particular deadline.
Nonetheless, it is important to remember that ‘By’ should be used in a sentence when the referred task must be completed ‘prior to or at the last moment’ of the given deadline. Conversely, ‘before’ should be used in a sentence when the referred task is supposed to be completed prior to the arrival of the given deadline.