Dear xql <[log in to unmask]>,

The example is not a very good one; it is not a good analogy.  The
relationship between electricity and agriculture is not very similar to the
relationship between blood and the body.  In agriculture, diesel fuel or
water itself, or even (n some regions of the world) human labor, would be
more similar to blood in the body.  Electricity in a machine or a system of
wiring (in contrast to agriculture) could be a better analogy to blood in
the body.  Even so, it would still not be very good.

But your question, technically, has to do with the form of analogies, which
can be expressed as a formula:

W is to X as Y is to Z

or, more technically,

W:X::Y:Z


Your own example should be written

Electricity is to agriculture as blood is to the body.

There should not be a "the" before agriculture because agriculture refers
to a very broad range of activities -- a whole *field* of study.  There
must be a "the" before body because it is one single thing.

The answers that you were given to choose from are all wrong if you
consider them in relation to the formula.  However, choice A)like comes the
closest to the word "as" in the formula.  So A is the only possible correct
choice; but it is not as good as "as"!

The answer that you have available to you, then, would look like this:

Electricity is to agriculture like blood is to the body.

But please, when you say it yourself, use "as" in place of "like" and you
will be much more correct.

All the best in your study of English!

Your friend,

Paul Wilson


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Paul T. Wilson                                   [log in to unmask]
Professor of Reading                   Western Michigan University