什么是电池短路？短路时会出现什么现象？
（ 1 ）∠B+∠BCD=180°；（2）∠1=∠2；（3）∠3=∠4；（4）∠B=∠5．
能判定AB∥CD的条件个数有（ ）
-- I think your wife doesn't understand you.
-- On the c____, she understands me very well.
