Editing Dutch grammar (section)

===20–99===

The decades 20 to 90 are formed by adding {{lang|nl|-tig}} ("-ty") to the base number. However, some are slightly irregular: 20 is {{lang|nl|tw'''in'''tig}}, 30 and 40 are {{lang|nl|d'''er'''tig}} and {{lang|nl|v'''eer'''tig}} (comparable to 13 and 14 above), 80 is {{lang|nl|'''t'''achtig}}. The remaining decades, although spelled beginning with {{lang|nl|v}} and {{lang|nl|z}}, are often pronounced beginning with voiceless {{IPA|/f/}} and {{IPA|/s/}} even in dialects that do not devoice these consonants normally.

{|class="wikitable"
|-
! 10 !! 20 !! 30 !! 40 !! 50 !! 60 !! 70 !! 80 !! 90
|-
| tien || twintig || dertig || veertig || vijftig || zestig || zeventig || tachtig || negentig
|}

Combinations of a decade and a unit are constructed in a regular way: the unit comes first, followed by {{lang|nl|en}} ("and"), followed by the decade. No spaces are written between them, and a [[Diaeresis (diacritic)|diaeresis]] is added when necessary. For example:

* 28 {{lang|nl|achtentwintig}} ("eight and twenty")
* 83 {{lang|nl|drieëntachtig}} ("three and eighty")
* 99 {{lang|nl|negenennegentig}} ("nine and ninety")