In 1881, French chemist Camille Faure redesigned the rechargeable lead-acid battery. Faure’s design greatly increased the amount of electricity that the original battery, which the French physicist Gaston Planté fifteen years earlier, could hold.
- is inventing
- will invent
- invents
- had invented
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Solution walkthrough
- Choice D is the best answer.
- Faure redesigned the battery in 1881, and the original battery was invented “fifteen years earlier.” Notice that this is the only choice in the past tense.
- To indicate that a past occurrence took place before another past occurrence, we need to use “had” + the past tense form of the verb.
- This is called the “past perfect” tense.