Vocabulary consisting only from characters you are able to read

kanji kana meaning randomReload
空ける akeru vyprázdnit (láhev)ichidan, jlpt3, leda1, verb, vtrans
kita northjlpt5, leda1
青空 aozora modrá oblohaleda1, shizen
rei zero, noughtjlpt5
空く aku to become vacantgodan, jlpt3, jlpt5, leda1, verb, vintrans