1. The relative motion of the plates carrying these continents has been constructed in detail, but the motion of one plate with respect to another cannot readily be translated into motion with respect to the earth's interior.
【译文】这些大陆板块的相对运动已被详细阐述出来，但一个板块相对另一板块的运动还不能轻易地被解释为它们相对于地球内部的运动。
【析句】在这个用but连接的两个并列分句中，前一个分句主语的限定成分the plates带了一个现在分词短语，起修饰作用；后一个分句中注意谓语be translated into意为“被解释为”，这里的another指的是another plates。介词with respect to出现了两次，意思是“相对于......”。
【讲词】translate意为“翻译”，但它还可以表示“解释；调动；转换”。Today's low inflation and steady growth in household income translate into more purchasing power.（现今的低通货膨胀率和家庭收入的稳定增长转化成了更多的购买力。）It is important to have an ideal, but it's more important to translate it into reality.（理想固然重要，但把理想变成现实更为重要。）Her silence was translated as a protest.（她的沉默被认为是一种抗议。）Three years ago, he was translated to the countryside.（他在三年前被调到了乡下。）
2. Emerging from the 1980 census is the picture of a nation developing more and more regional competition, as population growth in the Northeast and Midwest reaches a near standstill.
【译文】1980年美国人口普查表明，随着东北部和中西部人口增长近乎停止，地区间的竞争越来越激烈。
【析句】这是主从复合句，逗号前面是主句，是个倒装句，主干结构其实是The picture is emerging from the 1980 census。of a nation developing more and more regional competition是定语，修饰the picture。as引导的从句（as population growth in the Northeast and Midwest reaches a near standstill）表示伴随。
【讲词】 picture除了“图像”以外，还可表示“情形”等，具体什么意思要看句子的表述。记住几个与picture有关的词组，如：come/step into the picture（引人注意，处于显要地位，成为其中一部分），not in the picture（不合适，不相干的，被抛弃；被拒绝；没有赢的希望）=out of the picture（不合适；不相干的，被抛弃；被拒绝；没有赢的希望），put/keep sb. in the picture（把基本情况告诉某人）。