Number + 趟 + Noun
趟 (tàng) is a measure word used to count trips, journeys, or runs. It is placed after a number and before a noun describing the trip, such as a bus ride or a journey. It emphasizes the act of making a round trip or a single pass.
他今天跑了三趟超市才买齐了所有东西。
Tā jīntiān pǎo le sān tàng chāoshì cái mǎi qí le suǒyǒu dōngxi.
He made three trips to the supermarket today before he got everything.
这趟火车是直达北京的,不用中途换车。
Zhè tàng huǒchē shì zhídá Běijīng de, bùyòng zhōngtú huàn chē.
This train goes directly to Beijing; there's no need to transfer along the way.
我上个月出了两趟差,累得不行。
Wǒ shàng gè yuè chū le liǎng tàng chāi, lèi de bùxíng.
I went on two business trips last month and was exhausted.