【英语hundredthousandmillionbillion1,900读成onethousandandninehundred还是onethousandninehundred.3,400,080,200读成threebillionandfourhundredandeightythousandandtwohundred还是threebillionfourhundredeightythousandtwo】

　　英语hundredthousandmillionbillion

　　1,900读成onethousandandninehundred还是onethousandninehundred.

　　3,400,080,200读成threebillionandfourhundredandeightythousandandtwohundred还是threebillionfourhundredeightythousandtwohundred

　　129,200,006,001又该怎么读?

　　为什么1900没and而后面两个数字在百进千的时候加and呢

　　这个and什么时候用什么时候不用都搞混了！