The simple past tense is formed by adding -ED to the verb. However, with some verbs, you need to change the ending a little.

ක්‍රියාව අගට -ED යෙදීමෙන් අතීත කාලය සකසා ගනී. සමහර පද වලදී ක්‍රියා පදයේ අක්‍ෂරද වෙනස් කෙරේ.

Verb ending in...	How to make the simple past	Examples
e	Add -D	live - lived date - dated
Consonant + y	Change y to i, then add -ED	try - tried cry - cried
One vowel + one consonant (but NOT w or y)	Double the consonant, then add -ED	tap - tapped commit - committed
[anything else]	Add -ED	boil - boiled fill - filled hand - handed