Question

Due to the slow-moving nature of tectonic plates, the oldest ocean crust is thought to date from the Jurassic period, formed from huge fragments of the Earth's lithosphere and lasted 200 million years.

• A. formed from huge fragments of the Earth's lithosphere and lasted 200 million years.
• B. forming from huge fragments of the Earth's lithosphere and lasting 200 million years.
• C. forming from huge fragments of the Earth's lithosphere and lasted 200 million years.
• D. formed from huge fragments of the Earth's lithosphere and lasting 200 million years.
• E. formed from huge fragments of the Earth's lithosphere and has been lasting 200 million years.

Hint:

When an action or state started in the past and continues to the present, use a present perfect tense (e.g., "has existed," "has been"). The simple past tense (e.g., "existed," "lasted") is used for actions that were completed entirely in the past.

Answer 1

Answer: (E)

Step 1: Understanding the Concept:
This question tests the correct use of verb tenses to reflect logical time sequences. The sentence describes an event that happened in the distant past (the formation of the crust) and a state that began in the past and continues into the present (its duration or existence).

Step 2: Detailed Explanation:
The sentence has two descriptive phrases for the ocean crust: its formation and its duration.
\[\begin{array}{rl} \bullet & \text{The formation happened in the Jurassic period, a completed past event. The past participle "formed" correctly modifies "ocean crust." } \\ \bullet & \text{The duration of "200 million years" is a period that started in the past and continues to the present (the crust still exists). This requires a present perfect or present perfect progressive tense. } \\ \end{array}\] Let's analyze the options based on this:
\[\begin{array}{rl} \bullet & \text{(A) "formed... and lasted..." The simple past tense "lasted" implies that the 200-million-year duration is over, which is incorrect. } \\ \bullet & \text{(B) "forming... and lasting..." The present participle "forming" implies the crust is currently being formed, which contradicts the information that it dates from the Jurassic period. } \\ \bullet & \text{(C) "forming... and lasted..." This combines the incorrect present participle with the incorrect simple past tense. } \\ \bullet & \text{(D) "formed... and lasting..." The participles are not parallel. "Formed" is a past participle modifying the noun, while "lasting" would need to be part of a proper verb phrase. } \\ \bullet & \text{(E) "formed... and has been lasting..." This option uses the correct tenses. "formed" describes the completed past action. "has been lasting" (present perfect progressive) correctly indicates a duration that started in the past and continues to the present. This is the most logical and grammatically accurate choice. } \\ \end{array}\]

Step 3: Final Answer:
Option (E) correctly uses the past participle "formed" for the completed action of formation and the present perfect progressive "has been lasting" for the duration that continues to the present day.