That
When a clause serves to limit or define the noun it is modifying, use that to introduce the clause.
The policy paper that Michael will introduce at next week’s meeting is under review. |
Without the clause “that Michael will introduce at next week’s meeting,” the meaning of the noun “policy paper” remains ambiguous. The likelihood for misinterpretation by the reader is great; accordingly, that should be used. Also, because the clause is essential to the meaning of the noun, do not use commas.
The two organizations that were founded at the Bretton Woods Conference were the International Bank for Reconstruction and Development and the International Monetary Fund. |
The that clause is essential to the reader’s understanding of the noun phrase “the two organizations”: It answers the question, “What two organizations?”