As your instructor(教师) advised, you ought to spend your time on something ____ researching into.
| A．precious | B．worth | C．worthy | D．valuable |
----What do you think of the new English teacher?
----____she is an elegant lady, she can be extremely difficult to work with.
| A．While | B．When | C．As | D．Even if |
My father retired in 2008, _____ he has been devoting his time to gardening.
| A．at which | B．since when | C．when | D．after that |
Anyone, once ____ positive for Ebola, the deadly disease, will receive free medical treatment from the government.
| A．testing | B．being tested |
| C．tested | D．to test |
—What about your self-drive trip yesterday?
—Tiring! The road is being widened, and we_________ a rough ride.
| A．had | B．have | C．would have | D．have had |
----Stay a bit longer, please. It's been such____pleasure having you here.
----Thank you, but I've got____early start tomorrow morning.
| A．the;an | B．/;an | C．a;an | D．/;the |