The last thirty years _________ the quick development in almost every field in China.
It’s always difficult to live in a foreign country, ______ when you don’t speak the language.
He still remembers the place ______ we visited last year?
We won’t give up ______ we should fail 10 times.
The beauty of Hangzhou is ______ what words can describe.
The old man was the only person on the spot____ helped him ____ a series of facts as told