Not Necessary to Know My Name.

-In front of us is the Grand Teton National Park, which includes the major peaks of the Teton Range...
-Excuse me, Mark, what does Teton mean in English?
-Hmmm...well, actually, Teton is from French, means nipple.
 Even had been working as a quite competent tourist guide for years, Mark still seemed to be a little embarrassed to answer such a question.

When the sightseeing bus stopped, tourists were busy taking pictures.
-May I borrow your telescope for a minute, please?
Our guide suddenly asked, just before we got back to the bus.
-Sure.
I handed him the telescope. He looked, with a thoughtful and solemn mien.

The bus went along I-15, in most east California area, what we saw was a vast gobi desert, the Mojave Desert, dotted with drought-enduring creosote bushes and yucca. The tourists were about to fall into asleep.
-Look out from your left hand side, my friends, this is the helitherm system for heavy oil pipeline. As part of California state government's green technology program, the system used thermodiode solar plate to convert solar energy into thermal energy, heating the heavy oil line and keep the heat in the insulation layer, thus reduced the use of drag-reducer and enhanced the efficiency of oil pipelining. Though the California government tried to invest heavily on green energy, this new technology won't be easily popularized because of the low-yielding.
I lifted my eyes and saw a group of solar panels lying as an orderly matrix in the desert.

In Yellowstone National Park, after the tourists all feasted on the beautiful scenes, Mark started his so-called digression:
-Former Soviet astronomer Nikolai Kardashev once categorised the human civilization into three types: Type I civilization is one that controls the energy of an entire planet, this kind of civilization can control the weather, prevent earthquakes and mine deep in the earth's crust; Type II civilization is one that controls the power of the sun, which means directly utilise the power of the sun to drive its machines and begin to colonise the local star system; Type III civilization uses the power of the entire galaxy, and may probably has mastered Einstein's equations and can manipulate space-time at will. Our current civilization is equal to 0.7 comparing to this theory. Now we derive most energy from fossil fuels, and the day we exhaust the world's oil and coal is already can be seen. Not to mention the threaten from war and nuclear weapon. That's why the next 100 years is extremely important for the survival of our civilisation. The next 100 years! The fate of mankind will be determined by us, our sons and daughters and their next generation.
The silence in the bus lasted for a while.

On our way back to LA, we had a stop in Las Vegas.
-It's necessary for you to have a try of your luck, since you have been here, in Vegas. I can't teach you how to win, but I'm experienced to teach you how to lose. In fact, I've contributed most of my income here.

I talked with Mark later, and was surprised to know that he came from my hometown. He graduated from a key middle school there and went to U.S. in 1996, studying accountancy. I don't know what had happened all these years between his college and his current career-he seemed not willing to mention it. -How is your family? Mark gave a short laugh, said, I don't have a family yet. This time, it was my turn to feel much embarrassed.
I asked our guide, whether he could tell me his name.
-It's not necessary to know my name. If you want to do me a favour, please write me a good review on our website, I appreciate.
So that was what I did.