我wǒ 今jīn 天tiān 有yǒu 事shì，不bù 能néng 去qù。

I am busy today. I’m not able to go.

今jīn 天tiān is ‘today’.

有yǒu 事shì literally means ‘having things (to do)’. Here it means ‘busy’ . Of course the opposite of 有yǒu 事shì is 没méi 事shì which means ‘free’ or ‘not busy’.

You need to pay special attention to 没méi 事shì which also means ‘It doesn’t matter’ or ‘that’s O.K.’ when receiving apology, or ‘you’re welcome’ when being thanked.

能néng means ‘able to’.

去qù means ‘to go’.