Verb-noun combinations are insufficient fully to define an interaction. This is just the message that passes from the source to the target. If the source and target are not defined then the interaction is, at best, ambiguous. So:

	Ask what data or event pass from what to what across the system boundary?
	Always include the source and target
	Ensure that the sentence cannot be interpreted in more than one way
	Don't include things like 'The system verifies the customer'. It is not necessary to verify the information in the basic flow because we assume that all information entered is correct. Incorrect entries that will be detected, and the response will be defined, in alternate flows that handle these system exceptions.
	Do not use passive verbs. E.g. 'The customer is verified'. What does that mean? Yes it's a customer! We are defining a possible flow of events in terms of interactions across the system boundary and so only active verbs will suffice.
	Define a complete, accurate and unambiguous statement of what actually happens without describing how it is accomplished. This provides scope for the developer to decide what is the best way of implementing the interaction.