对我来说学普通话很困难。

Duì wǒ láishuō xué Pǔtōnghuà hěn kùnnan.

According to me, learning Mandarin is difficult.

如果你在生活中遇到困难你可以问我。

Rúguǒ nǐ zài shēnghuó zhōng yùdào kùnnan nǐ kěyǐ wèn wǒ.

If you run into difficulties in life, you can ask me.

我每天工作的时候都会遇到很多困难。

Wǒ měitiān gōngzuò de shíhou dōu huì yùdào hěn duō kùnnan.

I encounter many difficult situations at work every day.