The reason why Malaysia Airline Flight370 disappeared remained_____.
A.look into | B.to be looked into | C.looking into | D.to look into |
The momentJohn will never forget isMr. Smith gave him a lot of valuable advice on how to improve his writing.
A.that; that | B.that; when | C.when; that | D.when; when |
China first agreedthe six-party talks about North Korea nuclear weapons program.
A.to attend | B.to join | C.to participate in | D.to take a part |
It is wise of you towell trained workers for untrained ones in your workshop.
A.substitute | B.change | C.exchange | D.employ |
Many students listened to the lecture, but I wondered how much they.
A.took out | B.took up | C.took off | D.took in |
The customs office isyour luggage is inspected when you enter or leave a country.
A.where | B.when | C.why | D.who |