Correct

互相 vs 相互

/ hùxiāng vs xiānghù /
Strokes

Definition

互相 is an Adverb and 相互 is an Adjective, which means [mutually; each other]; both words mean “two or more people or things treat each other in the same way”.

Example

互相 is an Adverb and can only function as an adverbial; 相互 is an Adjective and can function either as an adverbial or as an attributive. 相互 is more literary.
Example ① is a very colloquial sentence, so 互相 is used; example ② is more literary, and either word can be used.
1
Jiě
姐弟
liǎ
dōu
zài
zhènshàng
镇上
shàng
zhōngxué
中学
  
,
yīnggāi
应该
xiāng
互相
zhàogu
照顾
  

The sister and brother went to the middle school in the town and looked after each other.

2
夫妻
jiān
yīnggāi
应该
xiāng
相互
  
(
xiāng
互相
  
)
liàng
体谅
  

Husband and wife should be understanding mutually.

互相 is used as an attributive.
3
企业
顾客
de
xiāng
相互
guānxi
关系
  
,
yīnggāi
应该
shì
彼此
xìnlài
信赖
  

The relationship between the enterprise and its clients should be trusty.

4
Tōngguò
通过
shíyàn
实验
  
,
tóngxué
同学
men
jìn
进一步
liǎojiě
了解
le
zhè
liǎng
zhǒng
zhì
物质
de
xiāngzuòyòng
相互作用
  

The students further know the interaction between the two substances through the chemical test.

5
Suīzhe
随着
zhōngguó
中国
jiā
加入
shìmào
世贸
zhī
组织
  
,
zhōngguó
中国
guó
国际
shèhuì
社会
zhījiān
之间
de
xiāng
相互
jiāowǎng
交往
huì
gèngjiā
更加
pínfán
频繁
  

With China's entry into WTO,she will communicate with the world more frequently.

相互 can be used together with 间 or 之间 as an attributive or adverbial.
1) 互相 cannot be an attributive by itself. We cannot say 互相关系 or 互相的感觉, etc., but we can say 互相合作的关系(the relationship of mutual cooperation), 互相信赖的感觉 (sense of mutual reliability), etc. Here 互相 is still an adverbial.

2) 互相 must be used with disyllabic or polysyllabic words and not with monosyllabic words. (互 is usually used with monosyllabic words to form four-character phrases, e.g. 互敬互让 yield to each other, 互有伤亡 the two sides at war suffered casualties, etc.)
6
Yào
chǔ
处理
hǎo
liǎng
dānwèi
单位
xiāng
相互
jiān
de
guānxi
关系
  

We should handle the mutual relationship of the two units well.

7
Liǎng
chǎng
de
chǎnpǐn
产品
xiāngzhījiān
相互之间
jìngzhēng
竞争
hěn
liè
激烈
  

There is a fierce competition between the products of the two factories.

Related

相互互相