Bangla numbers 20 to 29 (বিশ থেকে ঊনত্রিশ)

The first decade with a visible pattern. The residue of বিশ closes 21 through 28, and the unit word in front of it deforms: এক becomes একু-, দুই becomes বা-, তিন becomes তে-, ছয় becomes ছাব্‌-. Then 29 breaks out of the decade entirely — ঊনত্রিশ is built from thirty.