如图,AB∥CD,则∠1+∠3—∠2的度数等于 ____.
哺乳动物的牙齿分化为门齿、____和____.
All the children enjoy ____ (watch)TV.
Look, the computer ____ (be) red.
已知sinα=45,α∈(π2,π).
(Ⅰ)求sin(α﹣π6)的值;
(Ⅱ)求tan2α的值.