Relative clauses

Relative clauses

1. Used to link two sentences with a common IDEAIn 1937 H. Constant designed a compressor.This compressor / It ran in 1938 but failed mechanically.

Relative clauses

2. The relative pronoun replaces the common element the second time it appears

To join sentences using a relative:

1. Locate the first appearance of the common element. In 1937, H. Constant designed a compressor.

2. Add an appropriate relative after the common elementIn 1937, H. Constant designed a compressor

which...

To join sentences using a relative:

3. Add the second sentence MINUS the repeated elementIn 1937, H. Constant designed a compressor

which ran in 1938 but failed mechanically

Choice of relatives

Defining Non-defining

Antecedent: person

Who / that Who

Antecedent: object

Which / that Which

Defining vs non-defining

1. Non-defining clauses are NOT necessary to distinguish who/what you are talking about.

2. Non-defining clauses go between commas.

3. No “that” in non-defining clauses4. No omission of relative in non-defining

clauses.

Omission of relatives possible iff

1. Relative pronoun is who(m), which or that

2. No comma before the pronoun (therefore, defining clause)

3. There is a noun/pronoun (subject) between relative and verb.

Molecules absorb energy from the wall (that) they strike

Whose1. If the repeated element shows

possession, use “whose” as a relative adjective.

2. Whose is always followed by a name• Many high alloy steels are more

difficult to cut than mild steel.• Their ingredients retard oxidation.

→Many high alloy steels, whose ingredients retard oxidation, are more difficult to cut than mild steel.