The structures 只要…就… and 只有…才…
Both structures show the condition of an action, but they are used in different situations.
只要…就…
The structure 只要…就… 
is used in compound sentences. The first part of the sentence, after 只要, expresses the condition of an action., The second part of the sentence, after 就, expresses the the result of an action.
In these sentences there may be one or two subjects, or there may be none at all.
In the first part of the sentence, the subject can be placed before or after 只要. In the second part of the sentence, the subject must be placed before 就.
The structure is as follows:
is used in compound sentences. The first part of the sentence, after 只要, expresses the condition of an action., The second part of the sentence, after 就, expresses the the result of an action.
In these sentences there may be one or two subjects, or there may be none at all.
In the first part of the sentence, the subject can be placed before or after 只要. In the second part of the sentence, the subject must be placed before 就.
The structure is as follows:Scheme
subject 1
只要
condition
subject 2
就
result
Examples
你们只要努力，就一定可以成功
As long as you work hard, you will be successful
nǐmen zhǐyào nǔlì, jiù yídìng kěyǐ chénggōng
Or:
Scheme
只要
subject 1
condition
subject 2
就
result
Examples
只要他知道，就好了
As long as he knows, it’ll be okay
zhǐyào tā zhīdào, jiù hǎo le
只要你想去，我就跟你去
If you want to go, I’ll go with you
zhǐyào nǐ xiǎng qù, wǒ jiù gēn nǐ qù
只有…才…
The structure 只有…才… also shows the condition and result of an action. This result is only achieved if the condition of an action is met.
There is normally only one subject in these sentences, and it is placed before 才. Sometimes, however, there may not be a subject.
also shows the condition and result of an action. This result is only achieved if the condition of an action is met.
There is normally only one subject in these sentences, and it is placed before 才. Sometimes, however, there may not be a subject. Pay attention
The modal verbs 会 , 可以 , 能 are often used after 才.
, 可以 , 能 are often used after 才.Scheme
(subject)
只有
condition
subject
才
result
Pay attention
If the subject is in the middle of the sentence, there should be a comma before it.
If it’s at the beginning of the sentence or there is no subject, there is usually no comma.
Examples
只有你够努力，才可以通过考试
You can only pass the exam if you work hard
zhǐyǒu nǐ gòu nǔlì, cái kěyǐ tōngguò kǎoshì
有些人只有在压力下才工作得好
Some people can only work well under pressure
yǒuxiē rén zhǐyǒu zài yālì xià cái gōngzuò de hǎo
只有当山本坐在火车上时，他才意识到他要去哪里
It was only when Yamamoto was on the train that he realized where he was going
zhǐyǒu dāng shānběn zuò zài huǒchē shàng shí, tā cái yìshídào tā yào qù nǎlǐ
Another use of 只有…才…
只有…才… can be used to name a range of people or things who/which meet certain conditions. For example, ‘Only I can do this’.
It can also be used to set a time or a place limit. For example, ‘The office is only open on Tuesdays and Thursdays”.
Scheme
只有
A
才
B
Insert a person, thing, time or place for "A"; and the requisite conditions for "B".
Examples
只有他自己才明白
Only he himself understands
zhǐyǒu tā zìjǐ cái míngbai
只有足球迷才允许在足球俱乐部工作
Only football fans are allowed to work in football clubs
zhǐyǒu zúqiúmí cái yǔnxǔ zài zúqiú jùlèbù gōngzuò
我们只有在星期六才不用上学
It’s only on Saturdays that we have no school
wǒmen zhǐyǒu zài xīngqīliù cái bú yòng shàngxué
只有在春秋分点，白天和黑夜的时间才相等
The only time when day and night are of equal length are during the Spring and Autumn Equinox
zhǐyǒu zài chūnqiū fēndiǎn, báitiān hé hēiyè de shíjiān cái xiàngděng