【導讀】achancetomakeatripintospacewithmyfriendLiYanping,anastronomer.Wevisitedthemooninourspaceship!Beforeweleave,LiYanpingexplainedtomethattheforeceofthegravitywouldchangethreetimesonourjourneyandthatthefirstchangewouldbethemostpowerful.Thenwewereoff.Astherocketroseintotheair,wewerepushedbackintoourseatsbecauseweweretryingtoescapethepuloftheearth’sgravity.Itwassohardthatwecouldnotsayanythingtoeachother.

　　

【正文】 ri p to Canada to bi si t their cousi ns i n Montreal on the Atl anti c coast. Rather than take the aeropl ane al the way, they deci ded to fl y to Vancouver and then take the trai n west to east acros Canada. The though that they coul d cross the whol e continent was exci ti ng. Thei r fri end, Danny Li n, was waiti ng at the ai rport. H e was goi ng to take them and thei r baggage to catch “The True N orth”, the cross Canada train. O n the way to the stati on, he chated about thei r tri p. “You ’re goi ng to see som e great scenery. Goi ng eastward, you’l l pass m ountai ns and thousands of l akes and forests, as wel as wi de ri vers and large ci ti es. Som e people have the i dea that you can cross Canda i n l ess than fi ce days, but they fet the fact that Canada i s 5500 ki lom eters from coast to coast. H ere i n Vancouver, you’re i n Canada’s warm est part. Peopl e say it i s Canada’s m ost beauti ful ci ty, surrounded by m ountai ns and the Paci fi c O cean. Ski i ng i n the Rocky Mountai ns and sail ing i n the harbour m ake Vancouver one of Canada’s m ost popul ar ci ti es to l i ve i n. Its popul ati on i s i ncreasi ng rapi dl y. The coast north of Vancouver has som e of the ol dest and m ost beautiful forests i n the worl d. It i s so wet there that the trees are extrem ely tal l, som e m easuri ng over 90 m etres. ” That afternoon aboard the trai n, the cousins settl ed down i n thei r seats. Earli er that day, when they crossed the Rocky Mountai ns, they m anaged to catch si ght of som e m ountain goats and even a gri zzly bear and an eagl e. Their next stop was Cal gary, whi ch i s fam ous for the Cal gary Stam pede. Cowboys from al over the worl d e to pete i n the Stam pede. Many of them have a gi ft for ri di ng wi l d horses and can win thousands of dol ars i n pri zes. After two days’ travel, the gi rls began to real ize that Canada i s quite em pty. At school, they had l earned that m ost Canadi ans li ve wi thi n a few hundred kil om etres of the USA border, and Canada’s popul ati on i s onl y sli ghtl y over thi rty m il i on, but now they were amazed to se such an em pty country. They went through a wheatgrowi ng provi nce and saw farm s that covered thousands of acres. Afrer di ner, they were back i n an urban area, the busy port ci ty of Thunder Bay at the top of the Great Lakes. Because of the Great Lakes, they l earned, Canada has m ore fresh water than any other country in the worl d. In fact, i t has onethi rd of the worl d’s total fresh water, and much of i t i s i n the Great Lakes. That ni ght as they sl ept, the trai n rushed across the top of Lake Superi or, through the great forests and southward towads Toronto. “The True North” from Toronto to Montreal The next m orning the bushes and m apl e trees outsi de thei r wi ndow were red, gol d and orange, and there was frost on the ground, confi rmi ng that fal l had arri ved i n Canada. Around noon they ari ved in Toronto, the bi gest and m ost weal thy city i n Canada. They were not l eavi ng for Montreal until l ater, so they went on a tour of the ci ty. They went up the tal CN Tower and l ooked acros the l ake. In the di stance, they coul d see the Mi sty cl oud that rose from the great N i agara Fal s, whi ch is on the south si de of the l ake. The water fl ows into the N iagara Ri ver and over the fal ls on its way to the sea. They saw the covered stadi um , hom e of several fam ous basketbal team s. As they wal ked north from the harbour area, Li Dai yu sai d, “Li n Fang, one of my m other’s old schoolm ates, li ves here. I shoul d phone her from a telephone booth. ” They m et Li n Fei around dusk i n downtown Chi natown, one of the three i n Toronto. O ver di nner at a restaurant cal ed The Pi nk Pearl, the cousins chatted wi th Lin Fei , who had m oved to Canada m any years earl i er. “We can get good Cantonese food here, ” Lin Fei tol d them, “ because m ost of the Chinese peopl e here e from South Chi na, especi al l y H ong Kong. It’s too bad you can’t go as far as Ottawa, Canada’s capi tal . It’s approxim atel y four hundred kil om eters northeast of Toronto, so i t woul d take too l ong. ” The trai n l eft l ate that ni ght and arri ved i n Montreal at dawn the next morning. At the station, peopl e everywhere were speaki ng French. There were sighs and ads i n French, but som e of them had Engli sh words i n smal er l eters. “We don39。t l eave until thi s eveni ng, ” sai d Li u Qi an. “Let’s go downtown. Old Montreal i s close to the water. ” They spent the afternoon i n l ovel y shops and visi ting artists i n their workplaces beside the water. As they sat in a Buffet restaurant looking over the broad St Lawrence River, a young man sat down wi th them . “H el lo, m y name i s Henri. I’m a student at the uni versity nearby,” he said,” and I was wonderi ng where you are from.” The girl s told him they were on a trp across Canada and that they had onl y on day in Montreal. “That39。s too bad,” he sai d. “Montreal is a city wi th wonderful restaurants and cl ubs. Most of us speak both Engli sh and French, but the city has French cul ture and traditi ons. We l ove good coffee, good bread and good music.” That night as the transfer was speeding al ong a chance to make a tri p i nto space wi th m y fri end Li Yanpi ng, an astronom er. We vi si ted the moon i n our spaceshi p! Before we l eave, Li Yanpi ng expl ai ned to m e that the forece of the gravi ty woul d change three tim es on our journey and that the fi rst change would be the m ost powerful. Then we were off. As the rocket rose i nto the ai r, we were pushed back i nto our seats because we were tryi ng to escape the pul of the earth’s gravi ty. It was so hard that we coul d not say anythi ng to each other. Gradual l y the wei ght l essened and I was abl e to tal k to him . “ Why i s the spaceshi p not fal li ng back to the earth? O n the ear