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This is the Rachel's English 30-Day Phrasal Verb Challenge!

Learn 30 phrasal verbs in 30 days! Jumpstart your vocabulary in 2017. Today is Day 21 and we're studying phrasal verbs with "buy".

You don't have to buy up the videos in this phrasal verb vocabulary challenge, because they're absolutely free!

To buy up means to buy all of something that you can, quickly. This is a great deal. I'm going to buy up all these frames. Or, they're buying up all the empty lots in Philadelphia to build apartments.

To buy out means to buy all of someone's shares or stake in a company. I bought out my partner when she decided to retire. I bought all her shares, so now I own the whole company. It can also be when a large company buys out all of the stock of a smaller company, taking ownership. Or if one company simply buys another company. Instagram was bought out by Facebook.

If you buy somebody off, that means you pay that person, you give him money, so that they would do something or not do something for you. You bribe them. They wanted to buy me off, but I'm not going to take their money. I'm going to report their illegal activity. In other words, they wanted to pay me to keep quiet.

If you buy into something, you believe it. I bought into the idea that he was going to be a great president. Or, if someone's telling you something and it doesn't seem truthful, you can say, "I don't buy it." That's like saying, "I don't believe you."

Buy in can also mean to invest. I think you should by into this company, I really think the stock is going to go up.

We also use buy in with poker. If you want to join a poker game, you have to pay a certain amount of money to get chips to play with. That's so you can start playing. I'm going to buy into the game at that table.

The verb to buy back. This is when a company sells you something, and then when it's not useful to you anymore, they'll buy it back. For example, textbooks. You might find a store that will buy back your textbooks at the end of the school year, to sell them used.

BUY begins with the B consonant. Lips come together, bb, vocal cords vibrate, bb, buy– and release into the AI diphthong, buy. Jaw drops for the beginning of that diphthong, ba– back of the tongue lifts, ba– buy. Then the jaw comes up as the front of the tongue arches towards the front of the roof of the mouth. Buy, buy.

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Click the links in the description. This 30-day challenge is leading up to a phrasal verbs course that will be available on my online school on February 1. Rachel's English Academy is a collection of online courses focusing on English conversation, pronunciation, and listening comprehension. You will understand Americans better and speak better English with these courses. Visit rachelsenglishacademy.com to sign up and get started today.