Is “all that” or “all what” correct?

In English we say “everything that …”, for example “not everything we want can be bought”, and it is similar in some other languages, for example German. In English, however, we literally say “everything that …” (“all that”) and the “what” variant is wrong. For example, the saying “not all gold is gold that glitters” translates as:

  • All that glitters is not gold. (correct)
  • All what glitters is not gold. (incorrect)
  • All which glitters is not gold. (wrong)

Note here that the “all which” variant was historically used, but is now so archaic that it doesn’t sound natural either. If you feel the need (because of your Czech linguistic sensibilities) to start a subordinate clause in English after “all” with “what”, it usually sounds better to simply omit the conjunction:

  • This is all you need to know. (correct)
  • This is all that you need to know. (less elegant)
  • This is all what you need to know. (wrong)

The same goes for “everything”. For example, the sentence at the beginning of the article would most naturally be translated as:

  • Not everything we want can be bought. (correct)
  • Not everything that we want can be bought. (less elegant)
  • Not everything what we want can be bought. (incorrect)