The trailing I after the regex statement (which in this case is simply the phrase walmart) signifies that the statement is not case sensitive.

regex语句(本例中为walmart)后面的i表明该语句不区分大小写。

youdao

But I was invited to come, and I would say as a trailing spouse to become, to work as a counselor on the campus of Earlham College, which is a small, really wonderful and far reaching, -Wonderful, wonderful college.

而我是应邀前往，或者说,是当了个跟班的，做了顾问,留在了厄勒姆学院，这是一所规模不大，但非常优秀,影响广泛，-很棒，很棒的学校。

普林斯顿公开课 - 人性课程节选

If we talk about support levels real quick, I think with these indicators proving to be less reliable in turbulent markets, I personally have relied heavily on using trailing stop-loss orders, as I mentioned, as well as indicators like volume, price performance, and support levels.

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The two ropes I was trailing added even more weight to every move.

WSJ: Training for the Big Wall | By Michael J. Ybarra

It's cheaper than its peers at 8.1 times trailing earnings and 4 times what I think it should earn in 2013.

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