Question

20．據(jù)說(shuō)在許多西方國(guó)家13是個(gè)不吉利的數(shù)字． （It is said that…）
It is said that thirteen is an unlucky number in many Western countries．．

Answer 1

分析 It is said that thirteen is an unlucky number in many Western countries．

解答 答案：It is said that thirteen is an unlucky number in many Western countries．這里是說(shuō)客觀事實(shí)用一般現(xiàn)在時(shí)，表示據(jù)說(shuō)用所給的It is said that…，it是形式主語(yǔ)，that從句是真正主語(yǔ)，從句主語(yǔ)是thirteen十三，謂語(yǔ)動(dòng)詞用單數(shù)is，an  unlucky number一個(gè)不吉利的數(shù)字，地點(diǎn)狀語(yǔ)in many Western countries．許多西方國(guó)家，故答案是It is said that thirteen is an unlucky number in many Western countries．

點(diǎn)評(píng) it做形式主語(yǔ)，后面內(nèi)容做句子真正主語(yǔ)，除了由主語(yǔ)從句充當(dāng)之外，還可以由不定時(shí)，不定時(shí)短語(yǔ)，動(dòng)名詞以及動(dòng)名詞短語(yǔ)充當(dāng)，
例如下面句子
It is very useful to learn English so well 
It is the police's duty to protect the peope's life and properties