I enjoyed your lecture very much, ______ there were some parts I couldn’t quite understand.
—What did he say just now? —He said ___________________________.
The book _______ I found on my way home is my brother’s.
Armstrong became interested in _______ ever since he took his first _______ at the age of six.
How many times have youthe Science Museum?
If you want to go , the library is a good choice.