Everyone dreams about 20 percent of their sleeping time. 23 people who say they never dream show about 20 percent of REM sleep. 24 these “non-dreamers” do their sleeping in a laboratory 25 researchers can wake them up and ask them whether they were having dreams the moment before, it 26 that they dream as much as others.
答案：(D) turns out
【句型】it turns out that 固定句型「結果顯示/證明」；shows off（炫耀）、crosses out（劃掉）、brings up（提出/撫養）都不是這個固定句型的正確用法。
本題大考中心未公布逐題答對率，以下不談數據，只談觀念。
四個選項都是動詞加上一個小介副詞的片語動詞，長相整齊，會讓人覺得要一個一個比中文意思。其實這一格先看主詞就好——主詞是一個空空的 it，後面又跟著一個 that 子句，能走這個句型的動詞不多。
四個選項都是片語動詞，可見這一格考的是搭配，那就把句子結構拉出來：it ___ that they dream as much as others。主詞是 it，空格後面直接接一個 that 子句。這個 it 不是指前面的某樣東西，而是一個虛主詞，真正的內容在後面那個 that 子句裡。能走「it ＋ 動詞 ＋ that 子句」這個句型的說法有一組固定的成員，turn out 就是其中之一：it turns out that ...（結果發現、事實證明……）。另外三個選項都是及物動詞片語，後面一定要接受詞（show off your new phone 炫耀你的新手機），接不了 that 子句，也用不了虛主詞的 it。順便把同句型的其他說法一起記：it seems that ...（似乎……）、it happens that ...（碰巧……）、it appears that ...（看起來……）。turn out 另外還有 turn out to be（結果是）這個常見的變化形。
shows off（炫耀）：及物，要接受詞。crosses out（劃掉）：及物，要接受詞，語意也與研究結果無關。brings up（提出、扶養）：及物，要接受詞。三個選項的問題是同一個——它們都在等一個受詞，而空格後面給的是一個 that 子句。
it turns out that …（結果發現……）、turn out to be（結果是）、it seems that …（似乎……）、show off（炫耀）、cross out（劃掉）、bring up（提出、扶養）。
Basically, there are two kinds of sleep. One is Rapid Eye Movement (REM) sleep. In 21 , the brain waves of a sleeping person are similar to those of a waking person, and the eyes move about rapidly under the closed lids. 22 kind of sleep is Non-Rapid Eye Movement sleep.
Scientists have discovered that dreams happen mainly in REM sleep. Everyone dreams about 20 percent of their sleeping time. 23 people who say they never dream show about 20 percent of REM sleep. 24 these "non-dreamers" do their sleeping in a laboratory 25 researchers can wake them up and ask them whether they were having dreams the moment before, it 26 that they dream as much as others.
Events in daily life sometimes occur symbolically in dreams. 27 , a boy is having difficulties on the school playground because a bigger boy keeps bullying him. He may dream at night of being alone in the playground, 28 a lion. At other times the dreaded event from daily life simply occurs in a dream in its real-life form; 29 , the boy dreams of being bullied by the bigger boy.
30 scientific research, we have known more about the relationship between sleep and dreams. However, why a dream will take a certain symbolic form is still a mystery.