Except of the preposition, one says rather “do centra”, both is correct. There is only a slight, mostly negligible, difference in meaning. The first sentence with the singular form means “to do one particular shopping”, while the plural form stays for “to do more of shopping”.
That's what I'm doing today! I woke up late, 10 o clock! I have to hurry or all the shops will be closed!
Hm, German language has the same word for snake and queue, I didn't know this. But czech language doesn't
Weird.. I could have sworn my teacher told me it did.. i must have gotten it backwards. So how do I say I was in the queue for half an hour?
Queue in Czech is fronta or řada. Both are possible, fronta is IMHO more typical in this situation. Čekal(a) jsem ve frontě půl hodiny. Byl(a) jsem ve frontě půl hodiny.