读一读，写一写，注意找规律。1. twenty, nineteen, eight.een,___,____,____, .
2. two, four,__ __,____,ten,____,____.
3. eleven,__ __,___ _,_ __, fifteen, sixteen.
4. one, two, three, four,____,____,____.
5. nineteen, seventeen, _,_ ,eleven,_ .1. seventeen, sixteen, fifteen, fourteen
2. six, eight, twelve, fourteen
3. twelve,thirteen,fourteen
4. five,six,seven
5. fifteen,thirteen,nine