UniLang

Hey I used Google Translate so I dunno how accurate this is but I wanna ask
- How do I use it? (in reference to exercise equipment)
- Jak mohu používat?

Also, how would I say

- It is a nice day (in terms of weather)
- It's been such a nice day (in terms of weather)
- I love this song
- I'm exhausted

I don't want a word-for-word literal translation, just the sort of phrase a Czech would use in that situation.
Cheers!

1. Jak to mohu používat

2. Je hezký den / Dnes je hezky (today it is a nice day)

3. Dnes bylo (tak) hezky (I could translate it more exact, but that kind of sentence is not used very often)

4. Miluji tuhle písničku.

5. Jsem vyčerpaný / unavený.

How do I translate "grandma"/"grandpa"?

babička/dědeček
babi/děda