Not having much money, Mary decided to thumb a ride to New York.

玛丽因钱不多，决定搭便车到纽约去。

《新英汉大辞典》

Americans "thumb" a ride, while many Europeans wave the whole hand up and down when hitchhiking.

美国人用“大拇指”表示搭车，欧洲人要搭车时则是上下挥手。

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Since we ran out of gas, we were forced to thumb a ride into the city.

我们的车没油了，只得搭便车进城。

youdao

And Lindgren's aspirations for the season with Wolves will be boosted by the news that teenage sensation Tai Woffinden is defying doctor's advice and insisting he will continue to ride, despite thumb and shoulder injuries suffered during the midweek loss at Ipswich.

BBC: Lindgren thrilled with early form

We'll be in deep rural America for long stretches of the ride, which may, at times, limit my dispatches to thumb-driven blackberry notes.

WSJ: A Ride Across Iowa