The common ways to form the past tense in English are:

Regular verbs: Add -ed to the base form of the verb (e.g. walk - walked, play - played, study - studied).Irregular verbs: Have different forms changing the base form entirely (e.g. go - went, eat - ate, see - saw).The past tense of 'be': am/is -> was, are -> were (e.g. I was, she was, they were).Modal verbs: Use the past form of the modal verb (e.g. can - could, will - would, may - might).Past progressive tense: Use was/were + present participle (e.g. He was reading, They were eating).Past perfect tense: Use had + past participle (e.g. She had finished, They had left).

These are the most common ways to form the past tense, but there are also other forms and exceptions in English.