Both "一直" (yīzhí) and "一向" (yīxiàng) mean something close to "all along," and deal with continuous actions. However, their uses are different, and they are a pair of words that are often confusing. This article will clarify when you are supposed to use them.
"一直" means "straight" or "constantly" and it has the sense of doing something continuously "since a certain time". This means that something may have occurred, and then "一直" can be used with the action or habit since that point. It's important to note that this point in time doesn't necessarily have to be in the past, so "一直" can be used to say something "will happen repeatedly" in the future.
wǒ huì yī zhí péi zhe nǐ.
I will always be with you.
yǔ yī zhí zài xià, wǒ méi bàn fǎ chū qù.
It's constantly raining, I have no way to go out.
yī zhí wǎng qián zǒu, nǐ huì kàn dào dì tiě zhàn jiùzài nǐ yòu biān.
Keep walking ahead, you will see the subway station on your right.
tā bì yè yǐ hòu yī zhí méi yǒu zhǎo dào zhēn zhèng xǐ huān de gōng zuò.
He hasn't found a job that he really enjoys since his graduation from his college.
"一向" does not have the time constraint that "一直" has. Instead, it means that things have always been like they are. In this way, it is more like a habit. Furthermore, it is often used to express a habit or event that you don't like, and can also be used in conjunction with "不".
tā yī xiàng bú chí dào, zěn me jīn tiān hái méi dào?
He never comes late, how is it that he hasn't come yet today?
wǒ yī xiàng dōu bú xǐ huān chī hěn yóu nì de dōng xī.
I've never liked really greasy things.
wǒ men yī xiàng shuō huà suàn shù.
We always keep to our words.
tā zhè gè rén yī xiàng xǐ huān xuàn yào.
She has always liked showing off.
wǒ zhè gè péng yǒu yī xiàng dōu hěn dà fang.
This friend of mine is always very generous.
"一向" also can't be used to talk about constant future actions. For this kind of case, "一直" should be used instead.
Translated from: allsetlearning
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