słaba

feminine nominative/vocative singular of słaby

błyskawica

lightning bolt, lightning (weather phenomenon)

przestrzeń

1. space (area as a whole along with the objects within)
2. space (area between two objects) [+ między (instrumental) = between what]
3. space (all activities of a particular kind, often associated with a particular area)
4. space (unlimited physical extent)
5. expanse (vast, open area)
6. space (generalized construct or set whose members have some property in common)

popod

1. below, beneath, under [+instrumental] (denoting location)
2. below, beneath, under [+accusative] (denoting movement)
3. at a place where it takes little to no time to get somewhere; against, by, near, under [+instrumental]
4. towards a place where it takes little to no time to get somewhere; against, by, near, under [+accusative]

drzew

genitive plural of drzewo