It_______ ten years since Professor Du last_______ to the earth.
| A．was； came | B．has been； come |
| C．was, come | D．is； came |
Nobody has the right to laugh at others he is right．
A．until B．though C．if
Between the two hills there _____ a deep river.
A. are B. has C. is
—Tokyo will host 2020 Sumner Olympics．
—Really? It will befirst Asian city to host the Olympics twice．
A．a；a B．the；the C．the；a
—I hear your uncle works in Beijing. Can you tell me ________?
—For 5 years.
| A．when he went there | B．when he will go there |
| C．how soon he will come back | D．how long he has stayed there |
Please drink more water to keep healthy, ________ in summer.
| A．especially | B．probably | C．generally | D．possibly |