How to Conjugate "Cost" in English

by Craig Shrives

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Conjugation of "To Cost"

The verb "cost" is an irregular verb. (This means that "cost" does not form its simple past tense or its past participle by adding "-ed" or "-d" to the base form.)

The Five Forms of "To Cost"

FormcostAlternative Name
Base FormcostInfinitive Form
The -S FormcostsThird Person Singular Form
Past FormcostSimple Past Tense
The -ING FormcostingPresent Participle Form
The Past Participle Formcost[no alternative name]

"To Cost" in All the Tenses

The tables below show how "cost" conjugates in the past, present, and future tenses.

Past Tenses

PersonSimple PastPast Progressive TensePast Perfect TensePast Perfect Progressive Tense
  • I
  • you
  • he/she/it
  • we
  • you
  • they
  • cost
  • cost
  • cost
  • cost
  • cost
  • cost
The simple past tense is for a completed activity that happened in the past.
  • was costing
  • were costing
  • was costing
  • were costing
  • were costing
  • were costing
The past progressive tense is for an ongoing activity in the past. Often, it is used to set the scene for another action.
  • had cost
  • had cost
  • had cost
  • had cost
  • had cost
  • had cost
The past perfect tense is for emphasizing that an action was completed before another took place.
  • had been costing
  • had been costing
  • had been costing
  • had been costing
  • had been costing
  • had been costing
The past perfect progressive tense is for showing that an ongoing action in the past has ended.

Present Tenses

PersonSimple PresentPresent Progressive TensePresent Perfect TensePresent Perfect Progressive Tense
  • I
  • you
  • he/she/it
  • we
  • you
  • they
  • cost
  • cost
  • costs
  • cost
  • cost
  • cost
The simple present tense is mostly for a fact or a habit.
  • am costing
  • are costing
  • is costing
  • are costing
  • are costing
  • are costing
The present progressive tense is for an ongoing action in the present.
  • have cost
  • have cost
  • has cost
  • have cost
  • have cost
  • have cost
The present perfect tense is for an action that began in the past. (Often, the action continues into the present.)
  • have been costing
  • have been costing
  • has been costing
  • have been costing
  • have been costing
  • have been costing
The present perfect progressive tense is for a continuous activity that began in the past and continues into the present (or finished very recently).

Future Tenses

PersonSimple FutureFuture Progressive TenseFuture Perfect TenseFuture Perfect Progressive Tense
  • I
  • you
  • he/she/it
  • we
  • you
  • they
  • will cost
  • will cost
  • will cost
  • will cost
  • will cost
  • will cost
The simple future tense is for an action that will occur in the future.
  • will be costing
  • will be costing
  • will be costing
  • will be costing
  • will be costing
  • will be costing
The future progressive tense is for an ongoing action that will occur in the future.
  • will have cost
  • will have cost
  • will have cost
  • will have cost
  • will have cost
  • will have cost
The future perfect tense is for an action that will have been completed at some point in the future.
  • will have been costing
  • will have been costing
  • will have been costing
  • will have been costing
  • will have been costing
  • will have been costing
The future perfect progressive tense is for an ongoing action that will be completed at some specified time in the future.

Most Common Irregular Verbs

The two most common irregular verbs in English are "be" and "have." These pages give more details about these two verbs: Here are the next 10 most common irregular verbs in English:

Most Common Irregular Verbs

The two most common irregular verbs in English are "be" and "have." These pages give more details about these two verbs: Here are the next 10 most common irregular verbs in English:

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See Also

Parts of Speech Lists 200 Important Irregular Verbs Role-Play Scenarios for English Learners

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