A lecturer was giving a lecture to his students on stress management. He raised a glass of water and asked the audience, “How heavy do you think this glass of water is?” The students' answers ranged from 20g to 500g. It doesn't matter on the absolute {#blank#}1{#/blank#} (weigh). It depends on how long you hold {#blank#}2{#/blank#}. If I hold it for a minute, it is OK. If I hold it for an hour, I'll have {#blank#}3{#/blank#} ache in my right arm. If I hold it for a day, you will have to call an ambulance. It's the exact same weight, but the {#blank#}4{#/blank#} (long) I hold it, the heavier it becomes. If we carry our burdens {#blank#}5{#/blank#} the time, sooner or later, we won't be able to carry on, the burden {#blank#}6{#/blank#} (become) increasingly heavier. What you've to do is to put the glass down, rest for a while before holding it up again. We have to put down the burden periodically, so that we can {#blank#}7{#/blank#} (refresh) and are able to carry on.

    {#blank#}8{#/blank#} you return home from work tonight, put the burden of work {#blank#}9{#/blank#}. Don't carry it back home. You can pick it up tomorrow. Whatever burdens you're having now on your shoulders, let it down {#blank#}10{#/blank#} a moment if you can. Life is short, enjoy it!

    Everyone has his own way of saying things and his own special expressions. Many everyday American expressions are based {#blank#}1{#/blank#} colors. Red is a hot color. Americans often use {#blank#}2{#/blank#}to express heat. They may say they are red hot about something unfair. When they are red hot they are very {#blank#}3{#/blank#}(anger) about something. The small hot tasting peppers found in many Mexican foods {#blank#}4{#/blank#}(call) red hots for their color and their spicy taste. Fast loud music is popular with many people. They may say the music is red hot,{#blank#}5{#/blank#} (especial) the kind called Dixieland jazz. Pink is a {#blank#}6{#/blank#}(light) kind of red. People sometimes say they are in the pink {#blank#}7{#/blank#}they are in good health. The expression was first used in America at the beginning of the {#blank#}8{#/blank#}(twenty) century. It probably comes from the fact that many babies are born with a nice pink color {#blank#}9{#/blank#}shows that they are in good health. Blue is a cool color. The traditional blues music in the United States is {#blank#}10{#/blank#}opposite of red hot music. Blues is slow, sad and soulful(深情的). Someone who is blue is very sad.

    The polar bear is found in the Arctic Circle and some big land masses as far south as Newfoundland. While they are rare north of 88°, there is evidence {#blank#}1{#/blank#} they range all the way across the Arctic, and as far south as James Bay in Canada. It is difficult to figure out a global population of polar bears as much of the range has been  {#blank#}2{#/blank#} (poor) studied; however, biologists calculate that there are about 20,000-25,000 polar bears worldwide.

    Modem methods {#blank#}3{#/blank#} tracking polar bear populations have been employed only since the mid-1980s, and are expensive {#blank#}4{#/blank#} (perform) consistently over a large area. In recent years some Inuit people in Nunayut {#blank#}5{#/blank#} (report) increases in bear sightings around human settlements, leading to a {#blank#}6{#/blank#} (believe) that populations are increasing. Scientists have responded by {#blank#}7{#/blank#} (note) that hungry bears may be congregating(聚集) around human settlements, leading to the illusion(错觉) that populations are {#blank#}8{#/blank#} (high) than they actually are. Of {#blank#}9{#/blank#}  nineteen recognized polar bear subpopulations, three are declining, six {#blank#}10{#/blank#} (be) stable, one is increasing, and nine lack enough data.

    We walked inside a museum in Garden City and looked around, eager {#blank#}1{#/blank#} (meet) Kobie Boykins, a NASA engineer. He helped to design the Mars rover (探测器) Curiosity, {#blank#}2{#/blank#} is still exploring to this day.

    In a big presentation room, Boykins {#blank#}3{#/blank#} (talk) about the team's newest rover, Mars 2020. We asked him if the new rover would be {#blank#}4{#/blank#} most complicated one he and his team {#blank#}5{#/blank#} (make) so far. He told us that most of the engineering would be the same. However, the rover is still more {#blank#}6{#/blank#} (advance) and will be able to get more accurate test {#blank#}7{#/blank#} (result).

    When Boykins finished his presentation, some people brought him into another room where we would interview him. We asked if he felt he was {#blank#}8{#/blank#} a lot of pressure at work. He told us that he {#blank#}9{#/blank#} (actual) put a lot of pressure on himself. He said that working on the spacecraft wasn't putting him in that position, but he still wanted to make {#blank#}10{#/blank#} perfect.