It has been said that “happiness is like a butterfly, which, when________ , is always beyond our grasp, but which, if you will sit down quietly, may alight upon you.” (pursue)
Peter, together with his parents_________every Sunday.
It was not until everybody was present __________the party started.
If I had tried my best last term, I ________more progress then.
---The Bird's Nest, isn't it?---Yes. It's ___________we visited during our stay in Beijing.
---Did you have _______fun in Australia?--- Sure. It was ___________ unforgettable experience.