Compound nouns are made up of two nouns or an adjective and a noun, such as alarm clock or parking meter. They can be written as one, two or hyphenated words with no set rule, so a dictionary should be checked. The main stress is usually on the first part but sometimes both. Compound adjectives also combine two or three words, often with a present or past participle as the second part, and can include a hyphen before but not after a noun, with equal stress on both parts. Numbers can be combined with singular nouns to form compound adjectives like a five-minute walk.

1. COMPOUND NOUNS
• A compound noun is made up of two nouns, or an
adjective and a noun
For example, alarm clock, parking meter.
• Compound nouns are sometimes written as two words
(e.g., credit card), other times as one word
(e.g., sunglasses). Occasionally they are joined by a
hyphen (e.g., baby-sitter).
• There is no rule for this, so may need to check in a
dictionary.
• The main stress is usually on the first part (e.g., parking
meter), but sometimes it is on both parts (e.g., mother
tongue).

2. COMPOUND ADJECTIVES
• A compound adjective is made up of two different
words, and occasionally three. The second part of the
compound is often a present participle (e.g., looking)
or a past participle (e.g., known). Some compound
adjectives use a hyphen before a noun (e.g., a goodlooking man; a well-known actress), but not after a
noun (e.g., he is good looking. That actress is well
known.). The stress is usually equal on both parts of
the compound.
• We can combine a number and a singular noun to form
a compound adjective. We say a five-minute walk (not
a five-minutes walk)