Tense in speculative conditional sentences

Speculative conditional sentences, sometimes called unreal conditionals, show unlikely, contrary-to-fact, or impossible conditions. To show distance from truth or reality, English uses past or past perfect tense in the if clause, even for conditions in the present and future.

Unlikely possibilities

If the condition is possible but unlikely in the present or future, use the past tense in the if clause; in the independent clause, use would, could, or might plus the base form of the verb.

Example sentence: If I won the lottery, I would travel to Egypt. Explanation: The if clause is “If I won the lottery.” The result clause is “I would travel to Egypt.”

The writer does not expect to win the lottery. Because this is a possible but unlikely present or future situation, the if clause uses the past tense.

Example sentence: If Melinda drove a bit faster, we could get to the conference early. Explanation: The if clause is “If Melinda drove a bit faster.” The result clause is “we could get to the conference early.”

Conditions contrary to fact

In conditions that are currently unreal or contrary to fact, use the past-tense verb were (not was) in the if clause for all subjects.

Example sentence with editing. Original sentence: If I was president, I would make children's issues a priority. Revised sentence: If I were president, I would make children's issues a priority. Explanation: The verb “was” has been changed to “were.”

The writer is not president, so were is correct in the if clause.

NOTE:Do not use were in the if clause if the condition exists or might exist.

Events that did not happen

In a conditional sentence that speculates about an event that did not happen or was impossible in the past, use the past perfect tense in the if clause; in the independent clause, use would have, could have, or might have with the past participle.

Example sentence: If I had saved enough money, I would have visited Senegal last year. Explanation: The if clause is “If I had saved enough money.” The result clause is “I would have visited Senegal last year.”

The writer did not save enough money and did not travel to Senegal. This sentence shows a possibility that did not happen.

Example sentence: If Aunt Grace had been alive for your graduation, she would have been very proud. Explanation: The if clause is “If Aunt Grace had been alive for your graduation.” The result clause is “she would have been very proud.”

Aunt Grace was not alive at the time of the graduation. This sentence shows an impossible situation in the past.

Exercise: Verbs in conditional sentences

past participle A verb form usually ending in -d, -ed, -n, -en, or -t and functioning as part of a main verb or as an adjective: walked, broken, seen.