之所以……关键在于……

zhī suǒyǐ... guānjiàn zàiyú...

the key reason why... lies in... (之所以……关键在于……)

之所以 A，关键在于 B means “the key reason why A lies in B.” It highlights the decisive cause.

Anchor example

他之所以进步这么快，关键在于每天坚持练习。

Tā zhī suǒyǐ jìnbù zhème kuài, guānjiàn zàiyú měi tiān jiānchí liànxí.

The key reason he improved so quickly lies in practicing every day.

HSK 6

1 structures

15 exercises

Lesson summary

Read the sample sentence and notice how 之所以……关键在于…… works in the frame: 之所以 A，关键在于 B.

Explanation

之所以 introduces the result or phenomenon to be explained. 关键在于 introduces the core reason. Do not add 所以 after 之所以; this pattern already sets up an explanation. It is common in analysis and argumentation.

Structure Patterns

1 structures

Grammar pattern

之所以 A，关键在于 B

explains the decisive reason behind a result

他之所以进步这么快，关键在于每天坚持练习。

Tā zhī suǒyǐ jìnbù zhème kuài, guānjiàn zàiyú měi tiān jiānchí liànxí.

The key reason he improved so quickly lies in practicing every day.

Common Mistakes

Adding 所以: 之所以A，所以关键在于B。Do not add 所以 in this pattern.
Putting the reason before 之所以.之所以 introduces what needs explaining; reason follows 关键在于.

Usage Notes

Analytical and formal.
A is the result; B is the key reason.
Often used with 成功, 有效, 失败, 延期.

Practice

15 exercises

1 / 15

Fill in the blank:

他____进步这么快，关键在于每天坚持练习。

Back

之所以……关键在于…… (zhī suǒyǐ... guānjiàn zàiyú...) - HSK 6 | PandaBoo