56. Ultimately, however, our basic design strategy is focused not simply on being less bad but on creating completely healthful materials that can be either safely returned to the soil or reused by industry again and again.

　　【分析】本句為復(fù)合句。句子主干為our basic design strategy is focused not on being less bad but on creating healthful materials。that引導(dǎo)定語從句，修飾materials。however 意為 然而 ，是插入成分。not but 意為 不是 而是 ，連接兩個(gè)介詞短語。either or 意為 或者 或者 ，表示并列結(jié)構(gòu)。 【譯文】然而最終，我們的基本設(shè)計(jì)目標(biāo)不僅是簡單地關(guān)注于 較低危害 ，而是發(fā)明完全有益于健康的材料，這種材料或可以無害地回歸土地，或可以被工業(yè)重復(fù)利用。 57. As you sleep you pass through a sequence of sleep states light sleep, deep sleep and REM sleep that repeats approximately every 90 minutes. 【分析】本句為復(fù)合句。主句主干為you pass through a sequence of sleep states。as引導(dǎo)時(shí)間狀語從句，表示 當(dāng) 時(shí) 。that引導(dǎo)非限制性定語從句，修飾a sequence of sleep states，that在從句中作主語。light sleep, deep sleep and REM sleep 是插入成分，具體說明 states 的內(nèi)容。 【譯文】人們睡覺時(shí)經(jīng)歷了一連串的睡眠階段 淺度睡眠階段，深度睡眠階段，快速眼動(dòng)睡眠階段 大約每90分鐘重復(fù)一次。 58.You program the clock with the latest time at which you want to be wakened, and it then duly wakes you during the last light sleep phase before that. 【分析】本句為并列復(fù)合句。句子主干為You program the clock, and it wakes you。at which 引導(dǎo)定語從句，修飾 time，which 在從句中作時(shí)間狀語，at+時(shí)間是固定搭配，所以 which 之前加介詞 at，表示在某一具體時(shí)間點(diǎn)。句末的 that 指代 the latest time。 【譯文】將鬧鐘調(diào)好至你想起床的時(shí)間，它便會(huì)適時(shí)地在之前的最后一個(gè)淺眠期將你叫醒。 59. Home builders can now use materials such as paints that release significantly reduced amounts of organic compounds that don t destroy the quality of the air, water, or soil. 【分析】本句為復(fù)合句。主句為Home builders can now use materials。such as compounds是舉例說明，作插入語。第一個(gè) that 引導(dǎo)定語從句，修飾 paints;第二個(gè) that 引導(dǎo)定語從句，修飾 materials。 【譯文】房屋建造者們現(xiàn)在可以使用不破壞空氣、水或土壤的材料，如釋放少量有機(jī)物的涂料。

　　56. Ultimately, however, our basic design strategy is focused not simply on being less bad but on creating completely healthful materials that can be either safely returned to the soil or reused by industry again and again.

　　【分析】本句為復(fù)合句。句子主干為our basic design strategy is focused not on being less bad but on creating healthful materials。that引導(dǎo)定語從句，修飾materials。however 意為 然而 ，是插入成分。not but 意為 不是 而是 ，連接兩個(gè)介詞短語。either or 意為 或者 或者 ，表示并列結(jié)構(gòu)。 【譯文】然而最終，我們的基本設(shè)計(jì)目標(biāo)不僅是簡單地關(guān)注于 較低危害 ，而是發(fā)明完全有益于健康的材料，這種材料或可以無害地回歸土地，或可以被工業(yè)重復(fù)利用。 57. As you sleep you pass through a sequence of sleep states light sleep, deep sleep and REM sleep that repeats approximately every 90 minutes. 【分析】本句為復(fù)合句。主句主干為you pass through a sequence of sleep states。as引導(dǎo)時(shí)間狀語從句，表示 當(dāng) 時(shí) 。that引導(dǎo)非限制性定語從句，修飾a sequence of sleep states，that在從句中作主語。light sleep, deep sleep and REM sleep 是插入成分，具體說明 states 的內(nèi)容。 【譯文】人們睡覺時(shí)經(jīng)歷了一連串的睡眠階段 淺度睡眠階段，深度睡眠階段，快速眼動(dòng)睡眠階段 大約每90分鐘重復(fù)一次。 58.You program the clock with the latest time at which you want to be wakened, and it then duly wakes you during the last light sleep phase before that. 【分析】本句為并列復(fù)合句。句子主干為You program the clock, and it wakes you。at which 引導(dǎo)定語從句，修飾 time，which 在從句中作時(shí)間狀語，at+時(shí)間是固定搭配，所以 which 之前加介詞 at，表示在某一具體時(shí)間點(diǎn)。句末的 that 指代 the latest time。 【譯文】將鬧鐘調(diào)好至你想起床的時(shí)間，它便會(huì)適時(shí)地在之前的最后一個(gè)淺眠期將你叫醒。 59. Home builders can now use materials such as paints that release significantly reduced amounts of organic compounds that don t destroy the quality of the air, water, or soil. 【分析】本句為復(fù)合句。主句為Home builders can now use materials。such as compounds是舉例說明，作插入語。第一個(gè) that 引導(dǎo)定語從句，修飾 paints;第二個(gè) that 引導(dǎo)定語從句，修飾 materials。 【譯文】房屋建造者們現(xiàn)在可以使用不破壞空氣、水或土壤的材料，如釋放少量有機(jī)物的涂料。