Smile to the world, the world will smile back to you.
A. nor B. but C. or D. And
—How long will the summer English courses ? —For six weeks.
A. last B. open C. begin D. Start
For the present, I can’t afford ________ a car.
A. to buy B. buy C. buying D. for buying
I have been skating _______ nine o’clock.
A. for B. since C. at D. From
_____ have you been swimming? For five years.
A. How many times B. How long
C. How often D. How much
I hope _______more robots to help people in the future.
A. there were B. there will have
C. there will be D. there is
