the key to/一個a還是兩個a?/主謂搭配

本文首發於立文悉通微信公眾號（Transystom）

the key to

「the key to」在論文里也是很常用的一個片語，使用的時候要避免把to寫成不定式了，如：… is the key to improve prognosis，正確的寫法是「the key to」後面接名詞或動名詞。

… is the key to improving prognosis

… is the key to understanding the inflammatory processes

… is the key to achieving this goal

… is the key to extending the survival of patients

systematic review和meta-analysis

標題中 …: a systematic review and a meta-analysis不妥，第二個a不需要，直接寫成…: a systematic review and meta-analysis即可，因為meta-analysis是systematic review過程中用到的統計學方法，二者是相互結合的（Systematic reviews often, but not always, use statistical techniques (meta-analysis) to combine results of eligible studies, or at least use scoring of the levels of evidence depending on the methodology used. – Wikipedia ）。比如：a doctor and father（當醫生的父親），大概就是這麼回事。

關於systematic review和meta-analysis的關係可以參考文章：

http://www.qualitative-research.net/index.php/fqs/article/view/508/1096

http://drkuochinlung.blogspot.co.id/2013/11/review-articleresearch-article.html

yield/produce/lead to/result in

Therapy A yielded/produced/led to/resulted in a significantly higher survival rate than therapy B.

Patients treated with therapy A had/showed a significantly higher survival rate than those treated with therapy B.

survival rate是針對病人而言的，所以當主語是therapy的時候，不能用had/show，可以考慮用yielded/produced/led to/resulted in。