Professor Smith, along with his assistants, __ on the project day and night to meet the deadline.
| A．work | B．working | C．is working | D．are working |
Tangjialing was, until recently, _____ home to about 50,000 members of _____ant tribe ― low-income graduates, often born and raised in other cities.
| A．不填; a | B．a; the | C．不填; the | D．a; a |
It was not until the 1960s and 1970s archaeologists made real progress in understanding the script.
| A．when | B．which | C．how | D．that |
The couple are at the same age, but, the husband looks much older than his wife.
| A．in addition | B．in reality | C．in contrast | D．in detail |
After so many hardships, the scientist his motherland at last.
| A．set on his foot | B．set foot on | C．set feet on | D．set his feet on |
Sarah pretended to be cheerful, nothing about the argument.
| A．says | B．said | C．to say | D．saying |