Please help me with ADJECTIVES problem?

A compound adjective is when a two (or more) word combination is acting as a single adjective. There is a good description here, with examples and exercises: http://www.kentlaw.edu/academics/lrw/grinker/LwtaCompound_Adjectives.htm This page may also be useful: http://www.grammar-monster.com/lessons/adjectives_compound_adjectives.htm In "Her fifteen-minute presentation proved decisive to the outcome of the case.", "fifteen-minute" qualifies the noun "presentation" and cannot be split, so it is hyphenated to emphasise this. You will, however, often find examples of compound adjectives which are not hyphenated. Not all writers, even professional ones, keep to the rules (or even admit that there is one). You should learn to distinguish between compound adjectives (where the components should be hyphenated) and multiple adjectives, which are separated by commas: "The long-uncut grass was nearly up to my knees." "The long, uncut grass was nearly up to my knees." In the first sentence, "long-uncut" indicates that it was a long time since the grass had been cut ... that it had remained uncut for a long time. In the second sentence, the writer is saying that the grass was both "long" (in terms of length, not time) and "uncut".

Compound adjectives are adjectives that are made up of two or more adjectives, like the example you mentioned. The word "follow" is not an adjective. It is a verb. "Up" can be a preposition. So, the word "follow-up" is not a compound adjective.