English as a Second Language/By the time vs when


Dear Shannon,

What is the difference between these two sentences?

When we arrived at the airport, the flight had left.
By the time we arrived at the airport, the flight had left. (I'm not sure of the use of the past perfect here)

Thanks & best regards,
Antoine Ghannoum

The use of the past perfect is to show that the flight didn't leave immediately when you got to the airport, but sometime before your arrival.

As far as the difference between "when" and "by the time," there isn't really one.  We might prefer "by the time" to emphasize that it took longer than expected.

English as a Second Language

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Shannon Cole


I can answer questions related to learning the English and Spanish language.


I have taught ESL and Spanish since 1998 at the university and middle school levels. I am a native of the U.S., and have taught in both the U.S. and Mexico.

I am owner and operator of www.coleinstitute.com, an online language school.

Georgia TESOL in Action (1999)

B.A. in Spanish; M.Ed. in Language Education

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I have clients worldwide, some who want their documents proofread, and others who take lessons with me through the Internet. Some work at high-profile companies and government organizations. Besides the U.S. and Mexico, my recent students come from South Korea, Switzerland, Turkey, Colombia, Russia, Italy, Paraguay, China, Japan, the Philippines, and Saudi Arabia.

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