He is only too ready to help others, seldom, _________, refusing them when they turn to him.
Old people need special care in winter, as they are very __________ to sudden change of the weather.
Now more and more people have come to know the role that trees __________ in our natural environment.
My favorite cartoon character is Mickey Mouse. It's so __________ that we often feel __________.
A school should create all atmosphere __________ kids can develop themselves all round.
In summer, we can wear sunglasses to __________ our eyes from the strong sunlight.