(1) She broke the dishes when she was washing them.
(2) She broke the dishes when she washed them.
My textbook says (1) is correct and (2) is incorrect. But I found some sentences similar to (2). For example
When she washed the dishes, plates and bowls clattered as if they were breaking to pieces.
This is from Corpus of Contemporary American English.
Is (2) really incorrect?
The two sentences can mean subtly different things.
She broke the dishes when she was washing them.
There, the breakage occurred during a washing.
She broke the dishes when she washed them.
There, the breakage is said to have taken place at the time of their being washed by her.
The first emphasizes the ongoing nature of the wash. The second treats it as a discrete event. With the first, the breakage might be purely accidental. With the second, the breakage might be a direct result of the way in which she washed them.
When both events are expressed in the simple past, there is a possible sense that the two actions are correlated or coordinated, not merely coincidental.
Consider:
She decided he was a bore when he was describing the proper way to make a pancake.
She decided he was a bore when he described the proper way to make a pancake.
In the first, the decision occurs during the description. Perhaps it was long-winded? In the second, the decision occurs possibly as a result of the description. Perhaps it was the very subject of his conversation that resulted in her decision.
The second will do too. Although the first is better—We often use the past simple to talk about a completed past event and the past continuous to describe the situation that existed at the time. The completed event might have interrupted the situation, or just occurred while the situation or event was in progress.
When we talk about two past actions or events that went on over the same period of time, we can often use the past continuous for both: • Mario was working in a restaurant when I was living in London. However, we can often use the past simple to express a similar meaning: • Mario worked in a restaurant while he lived in London, (or ...was living in London.)
When we talk about two or more past completed events that follow each other, we use the past simple for both. The first may have caused the second: • She got up when the alarm clock went off. • He jumped out of bed and ran to see who the parcel was for.
