问题:
A. v(i)tal B. s(i)lent ...
问题:
A. (th)ere B. (th)ick ...
问题:
A. use(less) B. end(less) ...
问题:
A. c(oo)l B. fl(oo)d ...
问题:
A. ea(s)y B. noi(s)y ...
问题:
A. . walk B. .walking ...
问题:
A. . to lock B. locking ...
问题:
A. . would reach B. will have reached ...
问题:
A. took to B. took after ...
问题:
A. should know B. had known ...