You're focusing on theory. I'm focusing on how a person communicates. Let's look at an example. What functions do you think this writing demonstrates?
In the pre-dawn darkness, my three daughters and I huddled together in the cold mountain air. At an elevation of ten thousand feet, the wind was fierce and felt like it went right through us. We’d been warned about the frigid weather up here but still shivered in our fleece jackets and woolen hats. “Just imagine you’re somewhere warm,â€
I said to them. “Like Hawaii. Oh wait. We ARE in Hawaii!†I laughed at my own joke. They didn’t. A park ranger intoned ancient Hawaiian chants as the sun slowly rose over Mount Haleakala. The guidebook had described watching this sunrise as “spiritual†and life-changingâ€. I guess it should have been a magical moment but was too distracted by my chattering teeth to fully enjoy it. A few minutes later we retreated to the comfort of our rental car, thankful for the blast of warm air blowing on our frozen faces.
About an hour later, we were shedding our jackets and enjoying hot tea and crepes in the sun-filled courtyard of a cute café . We marveled over the now-perfect weather and talked about how we couldn’t wait to get back to the hotel to soak in the hot tub. (My husband was still there, snuggled cozily in bed. Rising at three in the morning to watch the sunrise wasn’t quite his idea of vacation fun.) As I looked at my daughters gathered around the table, it occurred to me that this was the first trip we had taken together where they were all now, unbelievably, adults - and that this might be one of our last family vacations that wouldn’t include son-in-laws or grandchildren. Not that I wouldn’t welcome them, but I was savoring having these wonderful girls all to myself on this beautiful island. And it dawned on me that maybe this was the magical moment I’d been looking for up on that mountain.