I can't tell you what she said. I've promised ________ it a secret.
A.keep B.to keep C.keeping D.kept
It may take _________ years to make such robots .
A.hundred of B.two hundreds C.hundreds of D.hundred
I can't tell you what she said. I've promised ________ it a secret.
A.keep B.to keep C.keeping D.kept
It may take _________ years to make such robots .
A.hundred of B.two hundreds C.hundreds of D.hundred