To do well on the SAT, you will need to master the correct usage of verb tenses. Even native speakers of English often make errors in verb tense. The most common errors tend to arise from confusion between three tenses: present perfect, past perfect, and simple past. The problem is that all of these tenses relate to the past in some way, but there are important differences between them.
Simple past is used for an action that happened in the past.
I went to Busan last weekend.
The Civil War began in 1861 and ended in 1865.
Present perfect is used for an action that began in the past and remains continuous or relevant in the present.
I have been married for 2 years.
I have lived in New York since 2015.
I have met many friends from other countries since I started college.
Past perfect is used for an action that began in the past and remained continuous or relevant at another date in the past. If that sounds complicated, it can help some students to think of it as double past.
I had been married for 2 years when I had my first child.
I had lived in New York for 5 years when I met my wife.
By the time the Civil War ended in 1865, over 600,000 soldiers had died.
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