填空。用所给词的适当形式填空（共10小题，每小题1分）
I have received your _______________(invite). Thank you very much.  
We’re _________ (plan) to visit France this summer.
He gave a detailed __________________(describe) of the thief.
At first nobody noticed the child’s ________ (appear). A few minutes later, his mother shouted, “ Where’s my child?”
_______________ (true) black flowers do not actually exist.
I have trouble ________(work) out the maths problem
Mary showed her ________ (confident) when she went into the room. 
There was an accident last night. __________ (lucky), the young man was not badly hurt.
I’ll do whatever I can ____ (improve)my English.
A letter of __________ (apply) is very necessary when your are finding a job.