The basic causes are unknown, although certain conditions that may lead to cancer have been ＿＿＿＿ A. identified B. guaranteed C. notified D. conveyed
A. B. C. D. 来源：www.examda.com
2.
The green house effect is caused by the higher ＿＿＿＿of CO2 in the atmosphere. A. consequence B. supplement C. assembly D. concentration
A. B. C. D.
3.
The destruction of these treasures was a loss for mankind that no amount of money could ＿＿＿＿. A. stand up to B. come up with C. make up for D. put up with
A. B. C. D.
4.
If we don t receive any reply by tomorrow morning, I shall have to ＿＿＿＿ him on the phone.
A. get to B. get onto C. get on with D. get over
A. B. C. D. 来源：www.examda.com
5.
As we are on the point of ＿＿＿＿ some important business with them, we should like to know exactly about their credit standing. A. transmitting B. transferring C. transacting D. transporting