by StaceyKoprince Mon May 11, 2009 4:50 pm
It might help to think of the meaning. "like" is used when you're trying to say something is similar to something else.
"as" is used in one of several ways:
- a conjunction in a clause (indicating a timeframe or causation, or indicating a comparison) (*Note: this is NOT the case you are asking about; this is with a clause, or a group of words containing a verb)
- a preposition with a noun or noun phrase (this is the case you are asking about)
In the latter case (preposition), "as" does NOT mean "similar to." So if the sentence wants something to say "similar to," don't use "as" - use "like." If the sentence wants to say something IS something else (not just similar to it), then use "as."
Example 6 is trying to say "similar to" - he thinks in a similar manner to a lawyer, but he's not actually a lawyer. So use "like."
Example 8 is not trying to say "similar to" - try it. The missing passenger is similar to a lawyer? No, the missing passenger actually is a lawyer - so use "as."
Example 9 is a comparison and the two items being compared are lawyers and doctors. The part before the comma ("lawyers") does not include any verb, so we cannot use "as" to set up the comparison because "as" can only be used in comparisons when we have two clauses, one for each thing being compared. So we're stuck using "like" here, because "lawyers" doesn't have a verb associated with it.
You could change the sentence to say:
As are lawyers, doctors are bound by a code of professional ethics.
Now, we have to use "as" because we have a clause ("are lawyers") before the comma instead of just a noun ("lawyers").
Does that help?
Stacey Koprince
Instructor
Director, Content & Curriculum
ManhattanPrep