The 之所以…是因为… structure
“Because...”
The 之所以…是因为… 
structure connects cause and effect.
In such a sentence, the focus is on the cause.
This structure is often used in formal speech.
structure connects cause and effect.
In such a sentence, the focus is on the cause.
This structure is often used in formal speech.Scheme
之所以
effect
是因为
cause
Pay attention
If there is a subject in the second part of a sentence, it is placed after 是因为.
Examples
这部电影之所以好看，是因为内容很有趣
The good thing about this movie is that it has interesting plot.
zhè bù diànyǐng zhī suǒyǐ hǎokàn, shì yīnwèi nèiróng hěn yǒuqù
你之所以能被录取，是因为你很优秀
You have been accepted because you are great
nǐ zhī suǒyǐ néng bèi lùqǔ, shì yīnwèi nǐ hěn yōuxiù
In the structure, 是因为 can be replaced with 是由于 .
.Examples
妈妈之所以生气了，是由于他不肯承认自己的错误
Mother got angry because he refused to admit his mistakes
māma zhī suǒyǐ shēngqì le, shì yóuyú tā bù kěn chéngrèn zìjǐ de cuòwù
小明之所以考差了，是由于他上课不认真
Xiao Ming failed his exams because he didn’t study hard
xiǎo míng zhī suǒyǐ kǎochà le, shì yóuyú tā shàngkè bú rènzhēn