A part of speech is a way of categorising words by their grammatical function. In English there are eight parts of speech: noun, verb, adjective, adverb, conjunction, preposition, pronoun and determiner.

A noun is a part of speech for identifying a thing, person, place or concept. Sometimes a noun can be made up of more than one word (known as a noun phrase).

A subject is a pronoun, noun or noun phrase which, together with the verb, make up a clause.

• It was such a fundamentally different technology that came in.
• The most obvious of examples is probably the Kodak case.

A verb is a part of speech that expresses some kind of action. There are two types of verbs: transitive (verbs which require an object) and intransitive (verbs which do not require an object).

• The new president prioritised education over military spending. (transitive: verb + noun)
• Despite assurances to the contrary, taxes increased. (intransitive)

Many verbs can be used both transitively or intransitively, which may indicate a change of meaning. Compare run in these examples:

• Most staff are not given specific training to run meetings. (transitive)
• The video clearly shows Walter Scott attempting to run. (intransitive)

An object is the noun or noun phrase which comes after the verb. There are two types: the direct object (which comes after the verb) and the indirect object (which comes after a preposition).

• They failed to introduce any breakthrough product into the market.

A complement is any word or phrase that completes a clause (essentially, anything that comes after the verb). It may be made up of a noun, a noun phrase, an adjective, adverb, an infinitive, a subordinate clause, or a combination of these.

• It is better to start our discussion with clear definitions of what is meant in this essay while referring to terms such as “disruptive technologies” or “incumbent firms”.

A clause is a grammatical unit that can express one whole idea. In English, a clause is made up of at least a subject and a verb. A main clause is a clause that can exist on its own, or as part of a longer sentence.

• This medium represents a disruptive technological change.
• Ferrari's dominance was due to their radical technology, which was unavailable to other competitors.

A subordinate clause cannot exist on its own and needs to be linked to a main clause.

• Ferrari's dominance was due to their radical technology, which was unavailable to other competitors.
• Although predicting the future performance of disruptive technology is difficult, there are factors which make this new technology unattractive for the established market players. 

A conjunction is a part of speech which links two clauses: coordinating conjunctions (e.g. and, or, but) link two main clauses and  subordinating conjunctions (e.g. although, in order that, if ... then ...) link a main clause with a subordinate clause.

• It was such a fundamentally different technology, so there was no way to use the old technology to meet the challenge.
• The Economist (2012) further explains how they failed to introduce any breakthrough product into the market.
• Whereas innovation and new products might mean there are new market entrants, it also means that those new entrants are usually the cause of the existing firms demise.