如果可能，应追查谣言的源头。If it's possible, track the rumour back to its origin.探险者在中非找到了尼罗河的几处源头.Explorers traced the Nile River to its several headstreams in Central Africa.我们溯河而上,直到源头.We traced the river to its source....
Contrast the formation of intrusive and extrusive igneous rocks.对比形成的侵扰和挤压火成岩.Its petrology , petrochemistry and geochemistry feature show the intrusive is post - collision and strongly - peraluminous granite.岩石学 、 岩石化学、...