The company has been _______ of President(总裁) Smith for 20 years and who will _______ it after his retirement?
.______two articles to write today,I have to stay at the classroom to make it.
----_____is it that is troubling Mary ? ----Working out the maths problem..
I wonder how long it will take you_____ such a hard task within so little time.
Tom was absent from school this morning, because sometimes he was a little weak and could ______ill .
. Will you pass me the dictionary _____ the cover is dark blue?