A trailer was attached to the rear of the truck.

卡车后面挂了一辆拖车。

《牛津词典》

He walked to his truck, put his hand on the trailer, said something that only the horses could hear, turned and walked back at a deliberate pace.

他走向自己的卡车，把手放在车厢上，说了些只有马儿才能听见的话，接着慢慢地走回来。

youdao

In many areas of the American West he still rides a horse, though he may carry it in a horse trailer behind his pickup truck to the point where the road gives out and a horse becomes indispensable.

在美国西部的很多地方他仍然骑着马，尽管也许是在一个马的拖车上去到没有路的地方，这时候马就变得必不可少了。

youdao

"Right now a tractor-trailer load of illegal cigarettes will net the truck driver about $2 million in profit."

VOA: standard.2010.08.11

In the truck trailer market, the weight is now 3, 500 pounds, up from 2, 916 pounds in 2006.

FORBES: Aluminum Usage In Cars To Grow -- Davenport & Co

Y. (AP) The driver of the minivan who was among seven people killed when a runaway truck trailer slammed into the vehicle in central New York was an aspiring mechanic heading home with his girlfriend and their friends and children who adored him, his mother said Friday.

NPR: Runaway Trailer Crashes Rare; NY Accident Killed 7

Each serves about 120 stores, and most of them have assigned a shipping dock to every store, with a truck-trailer parked waiting to fill up for a run.

FORBES: Merchant Princes