底

xǔ duō hǎi yáng lā jī dōu huì chén rù hǎi dǐ

许多海洋垃圾都会沉入海底。

A lot of Marine debris goes to the bottom of the ocean.

yī gè xiǎo hái bù shèn diào rù jǐng dǐ

一个小孩不慎掉入井底。

A child fell to the bottom of a well.

tā de xīn qíng shī wàng dào le gǔ dǐ

她的心情失望到了谷底。

Her disappointment was at its lowest ebb.

yuè dǐ

月底

the end of a month

liú gè dǐ

留个底

keep a copy

dǐ běn

底本

copy kept as a record

dǐ gǎo

底稿

draft

hēi dǐ bái diǎn

黑底白点

white spots on a black background

zhōng dǐ yú chéng

终底于成

succeed in the end

dǐ shì shāng gǎn

底事伤感？

Why is it sad?

mō dǐ

摸底

try to sound somebody out

lù dǐ

露底

reveal a secret

wǒ xīn lǐ yī diǎn r dǐ yě méi yǒu

我心里一点儿底也没有。

I am uncertain about it.