If you've studied Russian for a while you've probably noticed that this language is rich with prefixes and suffixes. By using them you can build new words. Today let's look at the prefixes без- and бес-.
без- and бес-
Both mean «without». They're similar to English -less, -free. They can be used in:
- nouns – безопасность, safety (без + опасность, danger); безработица, worklessness (без + работа, work)
- verbs – бездействовать, be inactive (без + действовать, to act)
- adverbs – безнадёжно, hopelessly (без + надежда, hope); бесследно, without a trace (без + след, trace)
- adjectives – бездомный, homeless (без+ дом, home); безоблачный, cloudless (без + облако, cloud).
Sometimes you just add the prefix to another word like in безопасность, sometimes you change the original word like in бездомный.
When to use без- and when бес-? It's pretty simple. Look at the next sound in the word. If it's a sonant or a vowel, use без-. If it's a breath consonant, you use бес-.
Russian sonants are:
Б, В, Г, Д, З, Ж, Й, Л, М, Н, Р