At __________ present we are going through a hard time, but I'm sure __________ things will get better in the near future.
--- The research on the new bird flu virus vaccine is challenging and demanding. Who do you think can do the job? ---____ my students have a try?
He is only too ready to help others, seldom, ____, refusing them when they turn to him.
Encouraged by my science teacher, I set about my studies on developing my product, _____I hope I will succeed in applying for a patent(专利).
The main reason why Apple’s products always manage to capture the imagination of people worldwide is their attention to _____. Each and every part of an Apple product is perfect in its body.
When a giraffe has _____ drink, it has to stand with its front legs wide apart in order to reach _____ water easily.