SAT文法知识系列栏目说明：每期分享3-5个文法知识点，帮助大家更好地备考SAT。

一、动词

时态一致

1. 含义：

前后句的时态要保持一致。

例如：People are queuing for the test right now so the organizer is asking everyone to wear masks.

2. 用法：

(1) 现在时

(1) 现在时

a) 一般现在时

i. 定义：经常性或习惯性的动作；普遍真理或一般规律。

ii. 动词形式：do/ does/ am/ is/ are

iii. 例句：

1. We often play football there.

2. I am a slow walker, but I never walk backwards.

3. The sun rises and the sun sets.

b) 现在进行时

i. 定义：此时此刻或目前一个阶段正在进行的动作；计划想要进行的动作。

ii. 动词形式：am/is/are doing

iii. 例句：

1. I am doing all I can to add value to the life of everyone I touch.

2. We are leaving on Friday?

3. He is always thinking of helping others.

c) 现在完成时

i. 定义：过去发生或已经完成的动作对现在造成的影响或结果，或从过去持续到现在的动作或状态.

ii. 标志词：already，by far，till now，since…，in/over/during/for the past/last...days/weeks/years…

iii. 动词形式：have/has done

iv. 例句：

 Qingdao has changed a lot in the last several years.

d) 一般将来时

i. 定义：将来发生的动作或状态；打算、计划或准备做某事。

ii. 例句：

1. It will rain tomorrow. 

2. I am going to challenge myself.

真题检测

真题检测 1

(2022-03AS-Q5) In other words, the scientists wondered whether dogs have expectations of what they search for or whether they simply have followed a trail of positive stimuli.

A. NO CHANGE

B. follow

C. will have followed

D. followed

解析：通过前半句whether dogs have expectations看出have是一般现在时，根据前后句的时态要保持一致的原则，后面的句子也要是一般现在时，所以排除A/C/D三个选项，所以选B。

注：2022-03AS-Q5为2022年3月亚太真题第5题。

真题检测 2

(2022-03AS-Q22) The results of the study certainly support Suveyke’s assertions that the career of a merchandise buyer is one that mixed creativity with business acumen all in a day’s work.

A. NO CHANGE

B. was mixing

C. mixes

D. had mixed

解析：通过the career of a merchandise buyer is one看出is是一般现在时，根据前后句的时态要保持一致的原则，后面的句子也要是一般现在时，所以排除A/B/D三个选项，所以选C。

注：2022-03AS-Q22为2022年3月亚太真题第22题。

真题检测 3

(2022-03AS-Q25) Proponents of the double-degenerate mode hypothesizes that in some cases the companion white dwarf survives and is propelled away with a velocity equal to its orbital velocity prior to the explosion.

A. NO CHANGE

B. has hypothesized

C. hypothesize

D. is hypothesizing

解析：通过and is propelled away with a velocity看出is是一般现在时，根据前后句的时态要保持一致的原则，前面的句子也要是一般现在时，所以排除A/B/D三个选项，所以选C。

注：2022-03AS-Q25为2022年3月亚太真题第25题。

真题检测 4

(2022-03AS-Q40) For each of those years, from 2014 to 2114, a noted author is to be asked to contribute an original piece of writing: each work is to be held securely.

A. NO CHANGE

B. are being

C. were

D. have been

解析：通过each work is to be held securely看出is to be是表示计划，根据前后句的时态要保持一致的原则，前面的句子也要是表示计划，所以排除B/C/D三个选项，所以选A。

注：2022-03AS-Q40为2022年3月亚太真题第40题。