The three modes are named muṭābaqah, taḍammun, and iltizām. A subtler question is how far each mode depends on linguistic convention and how far it involves reasoning from one meaning to another.
An internal component cannot be understood from a word unless its full conventional sense is first known. In that respect, convention is foundational. Yet moving from a whole to its component, or from a meaning to a necessary concomitant, also involves an intelligible relationship.
Technical traditions may emphasize these contributions differently. For initial classification, the secure criterion remains the distinction among whole, internal part, and external necessary concomitant. This distinction is essential when analyzing examples that combine linguistic convention with a further act of inference.