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 ______.

单项选择题The prediction process that the Jungners use is essentially ______.

单项选择题The results of the use of the Jungner apparatus indicate that ______.