Using when in adjective clauses. The type of adjective cost you will be learning is how to use when plus the subject and verb. Now what type of nouns do you think when modifies? Well, time words. Some examples of nouns of time include time, season, morning, period, moment, anniversary, year, month and day. But of course there are many other words that refer to time. Now, take a look at these different images, which time period do these images represent? The 1940s, the 1950s, or the 1960s? The correct answer is the 1950s. So let's talk about the history. Now one thing that I can say about the 1950s, is that the 1950s was a time when many great products were introduced, such as a color TV, Lego toy, car seatbelt and remote control. Now I think we can all agree that these are pretty great. Now I bet 1955, was a very exciting time for both children and adults because 1955 is the year when Disneyland opened. Also the 1950s was a period in history when some very important things happened. For example, DNA was discovered, also NASA was founded. And the polio vaccine was discovered saving hundreds and thousands of children. Now let's learn a little more about each of these events. Pay close attention to the use of when to form adjective clauses about time. The year when Cambridge scientists Watson and Crick discovered the chemical structure of DNA is 1953. Since then we have learned so much about all living things thanks to these scientists. October 1, 1958, is the date when NASA became operational to begin space explorations. Since then our understanding of our place in the universe has never been the same. The date when Dr. Jonas Salk announced the effectiveness of the polio vaccine on the radio is March 26, 1953. Thanks to Dr. Salk there are almost no known cases of polio now in the US. Take a look at these sentences. Where is the adjective clause? I've highlighted for you where the adjective clause begins and ends. Let's take a look. The year when Cambridge scientists Watson and Crick discovered the chemical structure of DNA is 1953. October 1, 1958 is the day when NASA became operational to begin space explorations. The date when Dr. Jonas Salk announced the effectiveness of the polio vaccine on the radio is March 26, 1953. Now do you remember what I said about these images? The 1950s was a time when many great products were introduced. Now let's talk about the adjective clause in this sentence. We have when, the pronoun, plus many great products, the subject, and were introduced, the verb and this adjective clause modifies time. Now the sentence is basically saying, the 1950s was a time many great products were introduced in that time. There are several different ways that you can express the same idea. The 1950s was a time in which many great products were introduced. Notice that with which, you should use a preposition, the appropriate preposition. The 1950s was a time that many great products were introduced. And the 1950s was a time many great products were introduced, using no pronoun. Using when and no pronoun are the most common forms. Let's take a look at another example. Let's combine these two ideas. 1955 is the year. Disneyland opened in that year. Do you remember how to complete this sentence? 1955 is the year when Disneyland opened. Here's some other ways that you can say the same thing. 1955 is the year in which Disneyland opened. Hmm, we can also say, 1955 is the year that Disneyland opened, or you can simply say, 1955 is the year Disneyland opened. Let me test your memory one more time. Combine these two ideas, the 1950s was a period in history. Some very important things happened in that time. Well the answer is, the 1950s was a period in history when some very important things happened. Well done. Well I hope you had fun going back in time with me. And I hope that you are more comfortable using, when in adjective clauses. Thanks for watching!
