Sometimes in English, we have "you won't see one without the other." In Chinese, the same sort of idea can be achieved using "少不了" (shǎobùliǎo). It means that if there is one thing, then there is going to be another something along with it.
英语里我们有时会说"you won't see one without the other"，中文里，相同的意思可以用"少不了"表达。它的意思是"如果有那么一件事，那肯定会有另一件事随之而来"。
The structure of this grammar point is pretty simple. The noun before "少不了" is sort of the "main" noun and the second noun is the one that tags along as a result.
Phrase 1, 少不了 + Phrase 2
guò nián zǒng shǎo bù liǎo dà yú dà ròu.
There's always a big meal when we celebrate the Chinese New Year.
tā xǐ huān chī cù, měi dùn fàn zǒng shǎo bù liǎo yī wǎn cù.
He likes to eat vinegar, there's a bowl of vinegar at every meal.
xué zhōng wén shǎo bù liǎo yào xué pīn yīn hé shēng diào.
Studying Chinese always involves studying pinyin and tones.
cóng zhōng guó huí qù yī dìng shǎo bù liǎo yào dài diǎn zhōng guó tè chǎn.
When you return from China, you will definitely have to bring back some distinctly Chinese products.
guò shēng rì zǒng shǎo bù liǎo shēng rì lǐ wù.
There are always birthday gifts when we spend birthdays.
Sometimes, the two things that "少不了" connects aren't objects. Instead they can be events. This construction is often based off of observations or experiences that the speaker has had, so that they can know what situations relate to each other. It is often used together with "又".
Situation 1 + 少不了 + (又) + Situation 2
Note, that in this construction, the reason follows "少不了"
bā diǎn duō le hái méi huí lái, shǎo bù liǎo yòu zài jiā bān.
It's past 8 o'clock he still hasn't come back. He must be working overtime.
kàn tā de yàng zǐ, shǎo bù liǎo yòu gēn nǚ péng yǒu chǎo jià le.
Look at how he looks. He must have argued with his girlfriend.
zhè me mèn rè, shǎo bù liǎo yào xià bào yǔ.
It's so stuffy. It must be about to storm.
jīn nián shǎo bù liǎo shì gè fēng shōu nián.
There's going to be a bumper crop this year.
Translated from: allsetlearning
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