等待 + 着 + Object
The verb 等待 (děngdài) means 'to wait' or 'to await.' It is a more formal synonym of 等 and is often used with 着 to emphasize the ongoing nature of the waiting. It can take a direct object indicating what or whom one is waiting for.
我们在机场等待了三个小时。
Wǒmen zài jīchǎng děngdài le sān gè xiǎoshí.
We waited at the airport for three hours.
他一直等待着她的回信。
Tā yìzhí děngdài zhe tā de huíxìn.
He has been waiting for her reply.
请耐心等待,医生马上就来。
Qǐng nàixīn děngdài, yīshēng mǎshàng jiù lái.
Please wait patiently; the doctor will be here soon.