Throughout my schooling, I was not taught to hyphenate my words. My boss however, continues to dictate that the following words, for example, should be hyphenated in our company material;

If you could please provide me with some explanation to the use of hyphens, that would be much appreciated.

That's rather a tall order, especially as, to some extent and in some contexts, the use of hyphens is discretionary. But we'll try to give you an overview.

There are probably three main areas where the hyphenation question arises, and they are compound nouns, compound adjectives and prefixes.

Compound nouns: these are nouns like call-back, hanger-on and work-flow.

There's a small problem here in that usage shifts. English has an agglutinative tendency; that is, words that go together tend to get joined together, first taking a hyphen and then becoming one word. So, work flow has become work-flow, but will probably end up as workflow (in line with workforce and workload). Therefore, some 'authorities' may take a more progressive stance than others. The best thing here is probably to just choose a dictionary you want to run with (Collins tends to be a bit more progressive than the Oxford) and be guided by that.

Compound adjectives: these are adjectives like heavy-duty, even-tempered, deep-blue, and your "much-loved" and "three-course".

These can be really snarly! The traditional rule is that when these adjectives appear before the noun, they are hyphenated: a heavy-duty battery, an even-tempered man, a deep-blue sea. When they follow the noun, they are not: the battery is heavy duty, the man is even tempered, the sea is deep blue.

The main rationale for the hyphen is that the two elements of the compound must be read together to have meaning, so the hyphen is used to indicate this. The battery is not a heavy battery, or a duty battery, but a heavy-duty battery; the man is not an even man and, although he could be described as a 'tempered' man (in that he has a temper of some sort), the meaning is that he is an even-tempered man. Of course, you can have a deep sea and a blue sea, and that brings us to the other main reason for the hyphen: to avoid ambiguity. If you mean the sea is dark blue rather than deep and blue, you need the hyphen. Similarly, if you wanted to talk about the services provided by your local city council, you would put a hyphen in 'local body services' to distinguish them from those provided by the local undertaker or massage parlour. (Some organisations these days apply only the ambiguity principle, ditching the hyphen anywhere where it's not necessary to prevent misunderstanding. This is arguably justifiable but is still a minority stance.)

However, there are exceptions to the above rule. One is when the first part of the compound is an adverb: a badly made shirt, a clearly marked boundary. Here, the adverb obviously qualifies the second part of the compound, so you don't need the hyphen. You can't have a badly shirt, or a clearly boundary. However, what about a well paid worker? This brings us to the exception to the exception: if the adverb is not obviously an adverb and/or could have another meaning, you need the hyphen. There are well-paid workers and well (healthy), paid workers. (This, of course, is another statement of the ambiguity principle above.)

The other exception is when the compound is so common that it is immediately recognised as a unit, as in hot water cylinder, income tax bill and social welfare payments.

Going by the traditional rules, we would agree with your boss hyphenating three-course, but not much loved, because 'much' is an easily recognisable, unambiguous adverb.

Prefixes: the agglutinative principle applies here, too. The more a prefix like 'multi-' is used with a particular word, the more it is likely to lose its hyphen and form a 'solid' compound. So, if I look in my dictionary, some 'multi' words have a hyphen (eg, multi-angular) and some don't (eg, multinational). Again, authorities may vary and it's a matter of picking a dictionary and running with it.

Accordingly, 'on' as a prefix may or may not take a hyphen. However, we have never seen ongoing with a hyphen. We think your boss is behind the times with this one.

We hope that's some help to you!