. >> so, we have to learn what the characters mean, and then how to say it in pinyin, so there's a lot of different aspects to it than just learning uh, a different language. >> there are also a lot of different reasons why students decide to learn mandarin. >> the culture and the language has always really appealed to me. >> i really want to go to china. it's somewhere that i've always wanted to go, so i hope i'll get to go there one day and use it. a journey. experts say it's probably twice as hard to master as spanish or french. but that's not stopping many american students. the number of us learning mandarin has increased tenfold in recent years. zai jian. >> if you want to know how much a hummingbird weighs, check your pockets. a hummingbird weighs about what a penny weighs -- less than one tenth of an ounce. but they are hungry little creatures. everyday, they consume more than their weight in nectar. for us, that's like eating more than 33 large pizzas in a day. >> they are three little letters, but they can spell the difference between life and death -- cpr. i'll explain what