英語講義【80】形容詞從句的位置
在《容易犯錯的形容詞從句》一文里，知道形容詞從句總是跟在被修飾的名詞（即先行詞）后面。例如：
?、?Any change which causes the formation of new matters is a chemical change.（在主句主語的名詞之后）
?、?Plastics is an important material which is widely used in industry.（在主句補(bǔ)足語名詞之后）
?、?It has certain features that are easily recognised.（在主句賓語名詞之后）
在下列情況下，形容詞從句和所修飾的名詞隔開：
㈠被介詞短語隔開，如：
④ Magnets work through lines of force that extend between the two ends of the magnet.
?、?A molecule may be defined as the smallest particle of matter that can exist without changing its nature.
?、芾锏男稳菰~從句和先行詞lines被介詞短語of force 分離。⑤里的卻被另一個介詞短語of matter隔開。
㈡被分詞短語隔開，如：
?、?There is no method known to medical science today that can effectively cure cancer.
⑥里的形容詞從句和先行詞method之間被過去分詞短語 known to medical science today隔開。
上述兩種隔離情況可以理解，也被接受。
另外還有一種分隔情況，也偶爾見到，特別在科技英語中，但這種離異法，值得商榷。
例如：
⑦ Several other ideas came along that enabled engineers to design still smaller units.
?、?Ninety-six substances are known which chemists consider to be elements.
?、吆廷嗬锏男稳菰~從句和先行詞ideas及substances之間都被主句的謂語動詞came along和are known分開。
這類的分隔情況，多在主句謂語動詞是被動語態(tài)（the passive voice）時才出現(xiàn)，如例⑧，但謂語動詞是主動語態(tài)（the active voice）的話，也可以，如例⑦，只是數(shù)量少些。
為什么要把形容詞從句常見的位置和先行詞分開呢？主要原因是：先行詞所在的主句較短，而修飾先行詞的形容詞從句則很長。為了平衡主句和從句，才采用這方法。雖然如此，但它和一般的形容詞從句的位置有很多抵觸，恐怕引起混亂。
為了減少不必要的麻煩，最好改用別的句式。其中一個方法是將形容詞從句改為另外一個獨(dú)立的簡單句（如例⑨╆）；另一個辦法是采用并列句（如例⑩╇）：
?、?Several other ideas came along. Such ideas /They enabled engineers to design still small units.
?、?Several other ideas came along and these ideas enabled engineers to design still small units.
╆ Ninety-six substances are known. Chemists consider them to be elements.
╇ Ninety-six substances are known and chemists consider them to be elements.
在《容易犯錯的形容詞從句》一文里，知道形容詞從句總是跟在被修飾的名詞（即先行詞）后面。例如：
?、?Any change which causes the formation of new matters is a chemical change.（在主句主語的名詞之后）
?、?Plastics is an important material which is widely used in industry.（在主句補(bǔ)足語名詞之后）
?、?It has certain features that are easily recognised.（在主句賓語名詞之后）
在下列情況下，形容詞從句和所修飾的名詞隔開：
㈠被介詞短語隔開，如：
?、?Magnets work through lines of force that extend between the two ends of the magnet.
?、?A molecule may be defined as the smallest particle of matter that can exist without changing its nature.
?、芾锏男稳菰~從句和先行詞lines被介詞短語of force 分離。⑤里的卻被另一個介詞短語of matter隔開。
?、姹环衷~短語隔開，如：
?、?There is no method known to medical science today that can effectively cure cancer.
?、蘩锏男稳菰~從句和先行詞method之間被過去分詞短語 known to medical science today隔開。
上述兩種隔離情況可以理解，也被接受。
另外還有一種分隔情況，也偶爾見到，特別在科技英語中，但這種離異法，值得商榷。
例如：
?、?Several other ideas came along that enabled engineers to design still smaller units.
?、?Ninety-six substances are known which chemists consider to be elements.
?、吆廷嗬锏男稳菰~從句和先行詞ideas及substances之間都被主句的謂語動詞came along和are known分開。
這類的分隔情況，多在主句謂語動詞是被動語態(tài)（the passive voice）時才出現(xiàn)，如例⑧，但謂語動詞是主動語態(tài)（the active voice）的話，也可以，如例⑦，只是數(shù)量少些。
為什么要把形容詞從句常見的位置和先行詞分開呢？主要原因是：先行詞所在的主句較短，而修飾先行詞的形容詞從句則很長。為了平衡主句和從句，才采用這方法。雖然如此，但它和一般的形容詞從句的位置有很多抵觸，恐怕引起混亂。
為了減少不必要的麻煩，最好改用別的句式。其中一個方法是將形容詞從句改為另外一個獨(dú)立的簡單句（如例⑨╆）；另一個辦法是采用并列句（如例⑩╇）：
?、?Several other ideas came along. Such ideas /They enabled engineers to design still small units.
?、?Several other ideas came along and these ideas enabled engineers to design still small units.
╆ Ninety-six substances are known. Chemists consider them to be elements.
╇ Ninety-six substances are known and chemists consider them to be elements.
