let's______(完整形式)A.let us B.let does
What is she _______ now?A. do B. does C. doing
_________ is this? This is Billy.A. Where B. What C. doing
________ your friend American? No, he isn’t.A. Is B. Are C. Am
________ name is Sandy.A. She B. Her C. His
I’m ________ Canada. A. froms B. to from C. from