BBC ESL-Plurals, simple passive

I studied plurals. I answered crosswords.
The plural of
woman-women
wolf-wolves
photo-photoes
mouse-mice
butterfly-butterflies
bus-buses
child-children
tooth-teeth

I think it is so easy, but sometimes we can't use right plural when we make a sentence.

After that, I studied simple passive. There are 8 sentences, and I answered 6 right answer. This 6 sentences are..
-Romeo and Juliet was written by William Shakespear.
(Romeo and Juliet is the name of book. So it is singular.)
-These windows are cleaned every morning.
-Smoking is not allowed in this office.
-The post is delivered every morning.
-There are no newspapers left. The last one was sold five minutes age.

And I answered wrong sentences are..
-A bunch of flowers and a cheque forr $10,000 were presented to the winner.
-Five lucky winners were chosen at random.

So fun!