Directions: One underlined word or phrase has an error. Correct it. New York inventor Charles Fritts has created the first solar cell in 1883. Since then, other scientists have made many advances in solar technology.

Minor collisions between ships and icebergs ______ still common today.

Explorers ______ the wreckage of the Titanic in 1985.

Past Tense / Past Progressive

Directions: One underlined word or phrase has an error. Correct it. The European Union introduced the euro in 1999, and it was becoming common currency in 2002. Before 1999, people used different currencies.

Can parents treat all their children ______?

This test contains two types of questions: multiple choice and error correction. For multiple choice questions, simply select the correct answer for the blank. For error correction questions, write in the box the underlined phrase that contains an error, and also write the correction for it.

The WTO ensures that countries enforce ______ tariffs.

The downturn resulted ______ company layoffs.

Directions: One underlined word or phrase has an error. Correct it. At 7:15 p.m., a zookeeper at the San Diego Zoo was cleaning near the lion exhibit when she suddenly dropped her keys into the enclosure. Security guards were called immediately, but they didn’t come because they napped.