USING relative clauses is a very convenient way to load sentences with more information. They do their job quite well when only one or two of relative clauses are involved, as in this sentence: 'The car that figured in the smashup ran through the red light, first hitting the sedan, which rolled over on impact.' The first relative clause in the sentence is, of course, 'that figured in the smashup,' modifying 'car'; the second is 'which rolled over on impact,' modifying 'sedan.'

When we attach more and more relative clauses to the sentence, ambiguity and monotony, start getting into the picture. The sentence becomes progressively confusing until it breaks into an incomprehensible sprawl. See, for instance, the grammatical havoc that the addition of three more relative clauses can do to the sentence given earlier as an example: