Sigrid explains the meaning of "prop" as both a noun and a verb. Either one can come in handy.

In American schools, it's common for kids to have to learn the Preamble to the United States Constitution by heart. This song, from Schoolhouse Rock, is meant to give these kids a hand, even though it is a slightly abridged version.

Here are some words to help answer the question "Which one?" We distinguish between singular and plural as well as between something close to us and far away.

This song was written and sung by Bob Dorough. It teaches about the multiplication of 5 through a game of hide and seek, in which the seeker counts by fives.

Bob Dorough wrote and sang this song about the number "three," as a fun way for kids to learn their multiplication tables. It became the pilot episode for Multiplication Rock, the first season of the Schoolhouse Rock TV series.

Nouns are usually the first words we learn. The good news is that with nouns, we don't have to worry about gender in English. We do, however, have to be aware of gerunds that act like nouns but look like verbs, and countable or uncountable nouns.

Anna, from Cambridge University Press, explains how and when to use the Present Simple.

Annette explains three more colloquial contractions people use in everyday conversation: gotta [got to], gotcha [got you], and dunno [don't know]. She also gives us examples in context.

This song from Schoolhouse Rock is to help kids understand about bones. Without bones, we're just blobs. It was written by George Newall and sung by Jack Sheldon.

This song teaches about the digit 0, portrayed as a superhero, as well as multiplication by powers of 10. This song was voted the 11th best song on the 30th anniversary edition. Sung and written by Bob Dorough.

Sigrid explains what a limerick is, and how to write one. If you are so inclined, you can submit your limericks in the "comments" section of the video tab.

Career expert Nicole Williams explains the most important question in an interview and the kind of answer the interviewer is looking for.

"D" is a voiced consonant that sounds a bit different depending on its context in a word or sentence.

Career expert Nicole Williams gives us some simple but useful tips for making a good first impression at a job interview.

Nicole Williams goes through a couple of items you should include when writing your resume, as well as some things that are simply overrated.

Getting some perspective can be key in assessing your interview skills. Nicole Williams suggests having someone film you so that you can see what you should work on.

Richard Williams, better known by his stage name Prince Ea, is an American spoken word artist, poet, rapper, and filmmaker. He formed the "Make 'SMART' Cool" movement in 2009, which is dedicated to promoting the ideals of education, intelligence, unity, and creativity through hip hop.

Rachel takes us through different ways of pronouncing the "you" in the phrase "Nice to meet you," and introduces us to a new friend of hers.

Rachel gives some helpful tips on sounding more like a native speaker when you introduce yourself in English.

Presenting yourself in an interview is tricky. This video is a reminder to think about the things you say from the point of view of the interviewer. What you say is not necessarily what they hear!

Join Minoo and Rachel, who each have their own YouTube channel devoted to improving English pronunciation, as they come together to compare British and American English pronunciation.

Learn the most important things to keep in mind when working on your resume for job applications.

This video will teach you the different pronunciations of the word "the" in American English and when they are used.

Rachel's English: For some people, "s" and "sh" sound the same. As Rachel explains, the positions for these two sounds are quite different. Learn the difference in tongue and lip position, and practice with minimal pairs.