The country's railway system has launched online ticket-booking and a real-name ticket purchasing system, and _______ requires passengers to provide their ID numbers when buying tickets.
| A．which | B．that | C．what | D．this |
The voyages of travellers before the 17th century show that they were not ________ the sea even though they didn’t have modern navigational aids.
| A．at the expense of | B．at the risk of | C．in the way of | D．at the mercy of |
Jack went to college last year and left his parents ,____________ to return home until he achieves his goal.
| A．determining not | B．not determined | C．not determining | D．determined not |
Don’t worry too much about making ___ mistakes. They are ___ natural part of learning.
| A．/: a | B．the;/ | C．/; the | D．the; the |
The volcano erupted violently , yet the village at the foot of it should _________.
| A．come through | B．go through | C．get through | D．pass through |
Although the used car seems in good ____________,it cannot run too fast.
| A．state | B．situation | C．condition | D．occasion |