Article
Particles are auxiliary words in a language that do not describe or refer to a specific object or action. Rather, particles often mark grammatical structures and/or show how other words within a sentence relate to each other. Many particles are closely related to adverbs or conjunctions.
Some particles are extremely flexible in their meaning and can also serve other functions within a sentence, especially as conjunctions or adverbs. For example, the word כִּי can function as either a particle or a conjunction; the word עַתָּה can function as either a particle or an adverb; and there are others as well.
Note
The classification of these words (i.e. words called "particles" in this grammar) is a subject of much debate among Hebrew linguists. This is true even for particles which have a clear meaning and function. Other parsing systems may have different names for these groups of particles, may have different groupings, or may even parse an individual particle as another kind of word such as a noun, an adverb, a conjunction, or others.
Particles are sometimes paired together (or with conjunctions) to form compound conjunctions. Compound conjunctions are best understood as a single unit with its own range of meanings which may or may not overlap with the meanings of the individual particles themselves. When in doubt, it is recommended to consult and dictionary or lexicon to determine whether any particular occurrence of a particle stands alone or as part of a compound conjunction.