Tell me please if there is any difference in meaning between the following sentences.
In this class we are going to review everything we studied before.
In this class we are going to review everything we have studied before.
In this class we are going to review everything we studied earlier.
In this class we are going to review everything we have studied earlier.
There is no significant difference in meaning between the four sentences. Before = on a previous occasion; earlier = at an earlier time (which might be earlier this week, this term or this year!)
The choice of tense (studied or have studied) is not significant in this context either.
In this class we are going to review everything we studied earlier. is correct? Earlier doesn't relate to any specific time and it also connects the past with the present so Present Perfect sounds like a better option here.
The present perfect is used when the speaker has in mind or wishes to signal that the finished action or state occurred in some timeframe that has no terminal time boundary in relation to a main time period (now/time of speaking/in this class). The earlier/previous studying occurred in some timeframe (the semester/term of the course) which has not yet terminated, at least in some sense—or it’s not considered or not seen as important to specify.
We have studied it [e.g., earlier in the course/before this class in the course, with the course continuing at the time of speaking].
The past simple is used when the speaker has in mind or wishes to communicate that a finished event or state occurred in some timeframe which finished in the past—or it’s not considered or not seen as important to specify.
We studied it [in past classes, which have ended].
The “past simple-exact time” idea is only a sort of rule of thumb: a specific/precise time is sometimes specified, but this is not a reliable rule. It quickly breaks down under scrutiny: I was born in France. (No time or specific/exact time was specified, yet we must stretch to find narrow contexts in which the present perfect would be used here.)
The “connection to the present” notion likewise often makes little or no sense. *I was born in France” certainly has a connection to the present. I’m alive now. Any past thing we mention now has a connection ton the present: We’re mentioning it in the present!
American speakers of English more often interchange the two tenses, while British speakers of English face more strict pressures to make a choice and convey it via aspect.
Earlier and before have the same meaning in this context.
Well , Im going to explain grammatically
When we use simple past we should mention an Exact time or priod not an unknown time ... But
In Every-Day English we Sometimes use it for unknown times
Therefore when a teacher says We're going to review what we studied , He probably means "What we studied in the last Sessions"
In the second sentence "... We have studied before" Teacher Means "What we have studied in the last few sessions"
Third : "... We studied earlier"
Teacher starts explaining a new subject then goes to subject 2 and then 3 .. in the last 10 minutes he/she says We're going to review what we studied earlier..
All of this happend in One Session
Number Four means exacty like Number 2
Though These explanations were based grammatical principles
In every-day english we dont have to obey rules therefore dont get confused and dont be a Detail-oriented , Most of fhe time we use things which are grammatically Incorrect but others will always Get the point
