下列离子方程式书写正确的是 ( )
2HCO3-+2OH-+Ba2+=BaCO3↓+2H2O+CO32-
The children all turned ____ the famous actress as she entered the classroom.
Edward, you play so well. But I ______ you played the piano.
She brought with her three friends, none of ______ I had ever met before.
I tried phoning her office, but I couldn’t _______.
His sister left home in 1998, and _______since.