2.Riding camels across the desert is very difficult for us.The sun is baking the ground,because there are no clouds to block it.Suddenly,with a strong wind (61)blowing(blow) the sand around us,we feel temporary blindness.After the sandstorm is over,we can no longer recognize (62)wherewe are going.Tired,thirsty and (63)covered(cover) with sand,we have no choice but (64)to keep(keep) pressing our camels to walk on.After the sun goes down,we set up our tents for the night.(65)Since/As/Becausethere are no clouds to keep heat from escaping into the atmosphere,the temperature(66)varies(variety)a great deal between day and night.We continue our journey the next morning,(67)hoping(hope) that we will have better luck to find an oasis(绿洲).Then,suddenly we see in front of us (68)is
a blue lake surrounded by tall trees.We urge our camels to walk even (69)faster(fast).Yes!This is an oasis!We (70)are saved(save)!