备战GRE填空题不仅需要坚持练习，还要掌握很多词汇，希望同学们能够好好复习，沉着应考!下面为大家整理了GRE绿皮书中一些精选的六选二的填空题，供大家参考。

　　15. Since she believed him to be both candid and trustworthy, she refused to consider the possibility that his statement had been______.

　　(A) irrelevant

　　(B) facetious

　　(C) mistaken

　　(D) critical

　　(E) insincere

　　(F) hypocritical

　　16. While the delegate clearly sought to______the optimism that has emerged recently, she stopped short of suggesting that the conference was near collapse and might produce nothing of significance.

　　(A) substantiate

　　(B) dampen

　　(C) encourage

　　(D) elucidate

　　(E) rekindle

　　(F) check

　　17. Far from viewing Jefferson as a skeptical but enlightened intellectual, historians of the 1960’s portrayed him as______thinker, eager to fill the young with his political orthodoxy while censoring ideas he did not like.

　　(A) an adventurous

　　(B) a doctrinaire

　　(C) an eclectic

　　(D) a dictatorial

　　(E) a judicious

　　(F) a cynical

　　18. Rather than enhancing a country’s security, the successful development of nuclear weapons could serve at first to increase that country’s _________.

　　(A) boldness

　　(B) influence

　　(C) fragility

　　(D) responsibility

　　(E) moderation

　　(F) vulnerability

　　19. After a slow sales start early in the year, mobile homes have been gaining favor as______to increasingly expensive conventional housing.

　　(A) reaction

　　(B) an addition

　　(C) an introduction

　　(D) an alternative

　　(E) a substitute

　　(F) a challenge

　　20. Hydrogen is the ______element of the universe in that it provides the building blocks from which the other elements are produced.

　　(A) steadiest

　　(B) expendable

　　(C) lightest

　　(D) final

　　(E) fundamental

　　(F) essential

　　21. Psychology has slowly evolved into an______scientific discipline that now functions autonomously with the same privileges and responsibilities as other sciences.

　　(A) independent

　　(B) unusual

　　(C) outmoded

　　(D) uncontrolled

　　(E) inactive