Our grammar lessons on “Conditionals” continue! This week we are studying the last of the four conditionals. Make sure to read the articles on the First, Second, and Third Conditionals before reading today’s lesson on the Zero Conditional. If you do, you will be a Conditional Master! (Extra credit points if you can tell us which conditional that last sentence represents!)

Last week, we studied the Third Conditional, which is all about looking back on the past. Sentences such as “If I hadn’t stayed up so late, I wouldn’t have been so tired for the test” and “If I had known you were going to wear a fancy dress, I would have worn one, too!” are examples of this conditional. As we mentioned in the last grammar post, you can’t change the past, but we often look back and speak about the “what if” scenarios. This is why we use the Third Conditional.

The Zero Conditional is completely different. It is used to talk about things that are true; often, it is used to express a scientific fact.


Zero Conditional

The Zero Conditional has two possible forms:


[if/when + subject + simple present] + [imperative]

[if/when + subject + simple present] + [subject + present simple]

  • If you don’t water your plants, they die.
  • If it rains, the streets get wet.
  • If it gets below freezing, water turns into ice.
  • When he finishes the application, ask him to turn it in to their front desk.
  • When the guests arrive, offer them a drink and appetizer. 
  • If she is late, call me and let me know.  

Notice how both of these forms often do not refer to a specific event. Instead, they refer to a general truth. Also notice how you can use “if” or “when” to begin the conditional clause.


What is the best way to practice the Zero Conditional? There are two methods that work very well: pretend that you are a boss or a scientist. Both use the Zero Conditional often! Here are some examples of the Zero Conditional:


Your boss

“If my 2:30 appointment is late, let me know. If they are more than 15 minutes late, call them and reschedule the appointment for Friday. If they can’t meet on Friday, ask them to meet on Monday. If they can’t meet on Monday, tell them ‘tough luck’!”


A scientist

“Water freezes at 32 degrees Fahrenheit. If you leave an ice cube on the counter, it melts. When it melts, the molecules change their structure. If you heat water, the molecules change their structure again. If you heat water to 212 degrees Fahrenheit, water will boil. When water boils, it turns to vapor.”