The boys followed the marks that they ________, until finally they found their way back to the campsite.
| A．left | B．have left | C．had left | D．have been left |
Although the peak travel time for Chinese railway doesn't start until Jan 19 this year, people who're eager to get a seat on the train _______ already _______ their struggles.
| A．are; starting | B．has; started | C．have; started | D．are; started |
Whale beachings（搁浅）_______ be caused by factors such as illness, or disorientation（迷失方向）caused by extra noise in the oceans, ______ shipping or oil and gas drilling.
| A．might; from | B．will; by | C．should; in | D．shall; on |
Though measures have now been taken to prevent further price hikes, many people remain _______ over the rising cost of food.
| A．be concerning | B．concerns | C．concern | D．concerned |
—The singer together with her band _______ invited to the concert. Did you enjoy that party?
—No, no sooner _______ than they sang their top hit Oh My Baby.
| A．was; I had left | B．were; I have gone | C．was; had I left | D．were; did I leave |
Living in the dormitory means _______ to take care of yourself, understand each others' differences and share_______ interests.
| A．to learn, common. | B．learning, ordinary |
| C．to learn; ordinary | D．learning; common |