单项选择题Lead(metal) and lead(dog's head) are spelt in the same way, but pronounced differently. This kind of sense relation is called ______.
单项选择题The first known settlers of Britain were ______.
单项选择题The most obvious and rapid change in the development of a language takes place in the area of ______.
单项选择题The English Renaissance period was an age of ______.
单项选择题The main purpose of the passage is to ______.