情深似海是指一种深厚的感情，它可以比喻为海洋般的广阔和无穷尽。这个词语通常用来形容两个人之间的感情或者对某件事物的热爱程度。

How to pronounce: qíng shēn sì hǎi (音标：qíng shēn sì hǎi)

Usage: 情深似海通常用来形容两个人之间的感情，也可以用来形容对某件事物的热爱程度。

Example sentences:

1. 她和他之间的感情真是情深似海，无法用言语来表达。

Their love for each other is like the depth of the ocean, it cannot be expressed in words.

2. 她对音乐的热爱就像是情深似海，从小就梦想成为一名音乐家。

Her love for music is like the depth of the ocean, she has dreamed of becoming a musician since she was young.

3. 他们之间的友谊就像是情深似海，经历了风风雨雨却依然坚不可摧。

Their friendship is like the depth of the ocean, it has weathered many storms and remains unbreakable.

4. 她写下的这首歌曲充满了对家乡的怀念，歌声中流露出一种情深似海的感情。

The song she wrote is full of nostalgia for her hometown, and her singing expresses a deep love.

5. 他对她的爱就像是情深似海，无论发生什么都不会改变。

His love for her is like the depth of the ocean, nothing can ever change it.

Synonyms and usage:

1. 情意绵绵 (qíng yì mián mián) - to have tender feelings for someone or something

2. 浓情蜜意 (nóng qíng mì yì) - to have strong affection or love for someone or something

3. 爱意滔滔 (ài yì tāo tāo) - to have overflowing love for someone or something

Editor's summary:

情深似海是一个形容两个人之间感情或者对某件事物的热爱程度的词语。它可以用来形容深厚的感情，也可以比喻为海洋般的广阔和无穷尽。在使用时，可以搭配一些同义词来丰富表达。