Miss Sullivan clarified the science Project in Simple but vivid language so as to make it easier for teenagers ________.
16. It is reported that they ____ arms and began to fight against the invaders (侵略者).
15. ____ ! There is a train coming.
14. Believe it or not, it ____ to me that you are all mistaken about such data.
13. Don’t worry! I'll _____ his safety.
12. The teacher didn't _____ to my questions which were not too difficult for me to think over.