来自孙维銮的问题
请问这道关于时态的英语题目为什么选这个?—Hi,John,Ihavenotseenyouforalongtime.What_______recently?—Carryingonsomeresearchonwildlife.A.haveyoubeendoingB.haveyoudoneC.wereyoudoingD.didyoudo请问这道
请问这道关于时态的英语题目为什么选这个?
—Hi,John,Ihavenotseenyouforalongtime.What_______recently?
—Carryingonsomeresearchonwildlife.
A.haveyoubeendoing
B.haveyoudone
C.wereyoudoing
D.didyoudo
请问这道题为什么选A不选B?
