In our daily life, everyone fails every now and then. It is how you             that makes a difference.

react

replace

rely

request

考查动词词义辨析。句意：在我们的日常生活中，每个人都会时不时地失败，你对失败如何反应才是关键。A. react反应；B. repalce取代，代替；C. rely 依靠，依赖；D.request要求；根据“n our daily life, everyone fails every now and then”，应是“怎样做出反应”。故选A项。

______about wild plants that they decided to make a trip to Madagascar for further research.

So curious the couple was

So curious were the couple

How curious the couple were

The couple was such curious

Mary and her friend          a plan and gathered forty people from my company to help the homeless people at the Christmas party.

came up with

put up with

caught up with

kept up with

考查动词短语辨析。句意：玛丽和她的朋友想出了一个计划，在圣诞节聚会上，从我的公司聚集了四十几个人来帮助无家可归的人。A. came up with 提出；B. put up with 忍耐；C. caught up with追上，赶上；D.kept up with 跟上。下文“聚集人帮助无家可归的人”是想出的计划。故选A项。

People           about what our future will look like for thousands of years.

have been wondering

wonder

wondered

will wonder

考查动词时态。句意：数千年以来人们一直想知道我们未来是什么样子。根据时间状语 for thousands of years可知，描述从过去开始一直持续到现在的动作，用现在完成进行时。故选A项。

As crossing

While you cross

While crossing

Cross

这题考查时间状语从句的省略式，当主从句的主语一样时，可以省略从句的主语和be动词，这题的while crossing就省略了you are，句意是：当你过马路时，别忘了两边看看。选C。

Like other animals, we are          until we know it is safe to relax.

on purpose

on fire

on guard

on duty

考查介词短语辨析。句意：像其他动物一样，我们在知道安全的时候才放松警惕。A.on purpose 故意；B. on fire着火；C.on guard 警惕；D.on duty值班。结合后文we know it is safe to relax，可知我们在知道安全的时候才放松警惕。故选C项。