Noun + 下
The localizer 下 (xià) means "under," "below," or "beneath" when placed after a noun to indicate location. It functions as a position word that turns a noun into a location phrase. For example, 星空下 means "under the starry sky" and 树下 means "under the tree."
孩子们坐在大树下乘凉。
Háizimen zuò zài dà shù xià chéngliáng.
The children sat under the big tree to cool off.
她把钥匙放在枕头下了。
Tā bǎ yàoshi fàng zài zhěntou xià le.
She put the key under the pillow.
桥下有一条小船停在那里。
Qiáo xià yǒu yì tiáo xiǎo chuán tíng zài nàlǐ.
There's a small boat parked under the bridge.