1．They had a ____________(航行) in space last year．
答案：voyage
2．The ____________(精神) is willing but the flesh is weak．
答案：spirit
3．I don’t think I can move a step ____________(更远)．
答案：further/farther
4．The cause of the accident remained ____________(不知道的)．
答案：unknown
5．Remember to test your ____________(刹车) regularly．
答案：brakes
6．It’s ____________(骇人的) to think how easily children can be hurt．
答案：frightening
