这家伙总是乐于帮助别人。

Zhè jiāhuǒ zǒng shì lèyú bāngzhù biérén.

This fellow is always willing to help others.

那个家伙很擅长修理电器。

Nà gè jiāhuǒ hěn shàncháng xiūlǐ diànqì.

That fellow is good at repairing electrical appliances.

别担心，我认识这个家伙，他很靠谱。

Bié dānxīn, wǒ rènshí zhè gè jiāhuǒ, tā hěn kàopǔ.

Don't worry, I know this fellow, he is very reliable.