Words (for the Bhāṭṭa Mīmāṃsā authors) get connected into a complex sentence meaning through proximity (sannidhi), semantic fitness (yogyatā) and syntactic expectancy (ākāṅkṣā).
These three criteria correspond to the requirement of being uttered one after the other with no intervening time (unlike in the case of the words “a cow” and “runs” pronounced on two different days), being semantically fit to connect (unlike the words “watering” and “with fire”) and being linkable through syntactic expectancy (as in the case of a verb and its arguments).
It is in this connection noteworthy that the example of expectancy always refer to syntax rather than semantics and typically have a verb expecting a complement or vice versa.
The Prābhākara Mīmāṃsā authors also adopt the same criteria in order to rule the understanding of the sentence meaning out of the connected words and avoid the objections (mentioned above) about the fact that out of a random heap of words one would not know how to start to get to the sentence meaning.