Correct

长期 vs 长久 vs 长远

/ chángqī vs chángjiǔ vs chángyuǎn /
Strokes

Formula

1
从长远……

Definition

长期, 长久, and 长远 both are Adjectives, which means [a long period of time; long-term; long-range].

Example

长期, 长久, and 长远, the three words all mean "a long time", but 长期 is a non-predicate adjective, while 长久 and 长远 are ordinary adjectives.
长期 means "a long period of time" and is usually used as an attributive or adverbial.
1
xiǎng
zhǎo
cháng
长期
de
gōngzuò
工作
  

I want to look for a long-term job.

2
Zhè
fángzi
房子
cháng
长期
méiyǒu
没有
rén
zhù
  

The house has been empty for a long time.

3
Zhège
这个
wèn
问题
cháng
长期
kùnrǎo
困扰
zhāo
  

She has been plagued by the problem for a long time.

长期, sometimes it is used in the pattern 是……的
4
Gǎi
改革
de
rènwu
任务
shì
cháng
长期
de
  

The reform will take a long time.

5
Zhèxiàng
这项
dàikuǎn
贷款
shì
cháng
长期
de
  

The loan is a long-term one.

长久 means "a long time", usually with a subjective flavour. It can be used as an attributive, adverbial, complement and predicate.
长久 can take the place of 长期 in examples ⑥, ⑦, and ⑧. But 长期 sounds more literary and is not used very often.
6
men
我们
de
gōngzuò
工作
yào
yǒu
chángjiǔ
长久
  
(
cháng
长期
  
)
de
huà
计划
  

Our work needs a long term plan.

7
de
yǐngzi
影子
chángjiǔ
长久
  
(
cháng
长期
  
)
xiàn
浮现
zài
de
nǎohǎi
脑海
zhōng
  

Her image has lingered in my mind for a long time.

8
men
他们
de
guānxi
关系
néng
可能
wéichí
维持
de
hěn
chángjiǔ
长久
  
(
cháng
长期
  
)
  

It is impossible for their relationship to last too long.

9
Zhèzhǒng
这种
miàn
局面
huì
zhǎngjiǔ
长久
ma
  
?

Will the situation last long?

长期 and 长久 can take 以来 (since) after them.
10
Cháng
长期
  
(
chángjiǔ
长久
  
)
lái
以来
  
,
zhè
这里
zhí
一直
shǐyòng
使用
tàiyángnéng
太阳能
  

The solar energy has been used here for a long time.

11
cháng
长期
  
(
chángjiǔ
长久
  
)
lái
以来
  
,
zhí
一直
cóngshì
从事
jiàoxué
教学法
de
yánjiū
研究
gōngzuò
工作
  

He has been working on the research of teaching methodology for a long time.

长远 mean "long range or long term of the future time", and is used as an attributive, adverbial, complement, and predicate.
1) In examples ⑫ and ⑬ 长期 or 长久 can be used instead.

2) Since 长久 does not stress the span of time, it cannot be used instead in examples ⑭ and ⑮.
12
Dìng
huà
计划
yào
yǒu
chángyuǎn
长远
  
(
cháng
长期
  
)
  
(
chángjiǔ
长久
  
)
suàn
打算
  

Decision-making should be long-term-oriented.

13
Zhèzhǒng
这种
yōuliáng
优良
de
chuántǒng
传统
yào
chángyuǎn
长远
  
(
cháng
长期
  
)
  
(
chángjiǔ
长久
  
)
bǎochí
保持
xià
下去
  

The good tradition should be remained forever.

14
kǎo
考虑
wèn
问题
shí
fēn
chángyuǎn
长远
  

His consideration is farsighted.

15
Shíxiàn
实现
shìjiè
世界
píng
和平
de
hái
hěn
chángyuǎn
长远
  

It is a long way for the world peace to go.

长远 can be said as 从长远…… and is generally used as an adverbial.
从长远……
16
Zhè
shì
yào
cóng
chángyuǎn
长远
kǎo
考虑
  
,
néng
zhǐ
只顾
yǎnqián
眼前
  

This matter should be considered from a long point of view.

17
Cóng
chángyuǎn
长远
jiǎo
角度
kǎo
考虑
chéngshì
城市
jiànshè
建设
zhǎn
发展
wèn
问题
  
,
yào
bié
特别
zhòngshì
重视
shēngtài
生态
huánjìng
环境
bǎo
保护
  

From a long-term point of view, city construction and development should specially value the protection of ecology and environment.