>Michael Kirschner wrote:
 
> How does one explain the use of the present rather than the future tense
> in the subrdinate clause of the following:
>
> "I will search the guests as they leave to make sure that nobody walks off
> with any silver."
>
> An ESL student demands a clear explanation as to why we don't say ". . .
> that nobody will walk off with any silver."
 
>Mary Ann Black replied:
>What would be wrong with saying " has walked off."  It seems to me
>that the present perfect fits here since technically  the person
>would have picked up the silver before leaving the room.  What do
>you think?
 
Replying first to Michael's question can help me establish the
framework for replying to Mary Ann's.  I draw my answer from a work
by Ilse Depraetere, _The Tense System in English Relative Clauses_
(1996).  Depraetere's work is based on a study of a large corpus of
written and spoken English analyzed within the framework of Renaat
Declerck's _Tense in English: Its Structure and Use in Discourse_
(1991).  In the case of the sentence cited by Kirschner, Declerck
(and Depraetere) would say that the verb tense in the subordinate
clause is temporally subordinated to the time of orientation
established by the verb tense in the main clause.  There is
in the subordinate clause a shift of perspective--we are now
transported to the future and 'experiencing' (as it were) the future
as if it were present.  The present tense is used to indicate that
the situation in the subordinate clause is simultaneous with the
situation represented in the main clause.  Thus, the 'walking off' is
represented as simultaneous with the 'searching.'
 
Contrast two sentences given by Declerck:
They will believe that Jack is back in town.
(Jack's presence in town is simultaneous with their believing it.)
          BUT
He will say that he will never leave her.
(The situation of his potentially leaving her is posterior to --even
further in the future than--the situation of his saying so.)
 
The past tense or indefinite present perfect are used in subordinate
clauses to indicate that the newly introduced situation is anterior
to the time of orientation specified by the future tense in the main
clause.  The following two sentences illustrate this principle of
interpretation:
(A pair of criminals have a conversation in which this line appears)
  The police will think that he was killed tonight.
        AND
 What will happen when the others have left?
( both the 'killing' and the 'leaving' are represented as having
occurred before the future time of orientation expressed in the main
clause.
 
 The problem with Mary Ann's suggestion of using the present
perfect is that the 'walking off' is then interpreted as occuring
before the searching can take place.  Thus, the intention of
searching is futile.  If the guests have walked off with the silver,
then it is illogical to suggest that they be searched.
 
So Michael, what can you tell the ESL student?  The answer is very
complex.  Simply put, you might say that some languages, like
English, have an elaborate system of temporal subordination, where
the verb in the subordinate clause is sometimes (but not always)
temporally subordinate to the verb in the main clause.  As part of
Depraetere's study shows, even native speakers of English do not
always agree 100% on the interpretation of tense sequences in main
and subordinate clauses.  Read Declerck and Depraetere and you will
begin to appreciate just how complex is the relationship between verb
tenses in main clauses and subordinate clauses.  Our abilities to
interpret the meanings of such sequences are amazing to me.  How
does a native speaker acquire such an amazing ability?  What does it
take for a non-native speaker to come close to acquiring this
competence in interpreting tense sequences?
 
Mike Medley
 
 
 
**********************************************************************
R. Michael Medley       VPH 211                Ph: (712) 737-7047
Assistant Professor     Northwestern College
Department of English   Orange City, IA  51041
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