【正文】 ?W: If we get there early enough, we won’t need them.M: I hope you are right.W: Don’t worry, if we have to wait, I’ll pay the bill.What would happen if they don’t get there early enough? –They may have to wait.When she went there two weeks ago, the service was awful.She has been there several times.Level 4 unit 1 part2ListeningToday Christina and her friend are enjoying themselves.This morning they got up very early and drove out of San Francisco.They crossed the Bay Bridge before the early morning mute and drove south. Because it was so early, there were almost no cars.How heavy was the traffic? –There were almost no cars.After driving for an hour and a half, they stopped and had breakfast.They ordered pancakes and coffee.They also had some fresh fruit.When they finished eating, it was seven o’clock.Then they got back into the car, and drove south.Christina wanted to listen to music, so they turned on the radio.An hour later, they stopped for gas.They noticed that there was also a charging station for electric cars.How did they order for breakfast? –They ordered pancakes and coffee.What did they do after they finished eating? –They got back into the car and drove south.It’s now 1:15 (one fifteen), and they are in Yosemite Park.They have been there for two hours, since 11:15(eleven fifteen).They are looking at Yosemite falls, which is the highest waterfall in the park.The water drops a total of 740 meters from the top of the upper fall to the base of the lower fall. When did they arrive at the park? –They got there at 11:15.In another fifteen minutes, they planned to eat lunch at a magnificent old hotel in the park.It was built in 1927 and has a great view.They wanted to stay there but they couldn’t get reservations.To get a room at that hotel, you usually need to make reservations several months in advance.When do you need to make reservations? –You need to make reservations several months in advance.Why couldn’t they get reservations? –They didn’t reserve early enough.They planned to stay in the park until around four o’clock.By then, they will have been in the park for nearly five hours.Then they will get back into the car and drive back to San Francisco.They plan to eat dinner somewhere along the way.If the traffic isn’t too bad, they should be back in San Francisco by ten o’clock.When do they expect to be back in San Francisco? –They expect to be back by 10 o’clock.How long would they have been in the park if they leave as scheduled? –For nearly 5 hours.Early tomorrow morning, they are going to cross the Golden Gate Bridge and go north along the coast.From some places you can look out on the ocean and see whales and other sea life.Christina has never seen a whale before, so she is looking forward to it.And tomorrow night they have something special planned.They are going to watch a baseball game.Christina has never seen a baseball game, but she has heard that it is very popular in the US. Andthe San Francisco baseball team is one of the best.What does she hope to see from the coast? –She hopes to see whales.What are they going to do tomorrow morning? –They are going to cross the Golden Gate Bridge.VocabularyA force is a push or a pull on an object.A force changes the motion of a moving object.A force can be strong or weak and it always has a direction.The Earth is a planet that goes around the sun in a circular orbit.The speed of its motion doesn’t change, but the direction of its motion does.The Earth has a layer of gas above its surface which helps to support life.Atoms are the building blocks of matter.At the center of an atom is its nucleus which has a positive electric charge.Outside the nucleus are electrons which have a negative charge.Asteroids and ets are objects that obey our sun, but are smaller than planets.Asteroids that pass close to the Earth are called nearearth objects.The layer of gases just above the Earth’s surface is our atmosphere.The atmosphere is made of gases such as oxygen and nitrogen. Withoutan atmosphere there would be no life on Earth.If they collide with Earth they could cause an extinction event.A force can increase or decrease the speed of an object, and it can change the direction of motion. Theelectric force between the nucleus and the electrons holds the atom together.The two lines on the left intersect each other at a right angle which is 90 degrees.The two lines on the right are parallel which means they never cross.The adjacent sides of a rectangle are perpendicular which means they meet a 90degree angle.The opposite sides of a rectangle are equal and parallel which means they never cross.The area of a rectangle is the length times the width.A circle is a two dimensional figure with a radius and a circumference which is the distance around the circle. Thearea of a circle is Pi R squared, where R is the radius and Pi is the ratio of the circle circumference to its diameter.A sphere is a three dimensional figure with a radius and a volume which is four thirds Pi R cubed.All points on the surface of a sphere are equidistant from its center.A right triangle is a two dimensional figure with three side, two of which are perpendicular.To find its area, multiply the length of the two perpendicular sides a and b and divide by 2, A equals 1 half ab.A rectangle is a 2 dimensional figure with 4 sides.DialogueM: Have you finished eating yet?W: No, I haven’t. Why are you in such a hurry?M: I’m sorry, but you are such a slow eater.W: A slow eater? Well, I try to enjoy my food. You just eat and swallow.I don’t see how you can even taste it.M: OK, I’m sorry. Do you mind if I get another glass of wine?W: No, go ahead. I don’t want you to sit there putting pressure on me. I thought we were going to hav