误：He took aim to (on) the bird but missed.
正：He took aim at the bird but missed.
析：take aim at(向…瞄准)是习语, 用介词 at。注意以下各例中 aim(用作动词或名词)也与介词 at 搭配：He aimed his gunat the bird, but did not fire.(他用枪瞄准鸟, 但没开枪)。/ When the teacher said that there was a lazy boy in the
class, he was aiming at John.( 当老师说班上有个不用功的孩子时, 他是针对约翰说的)。
误：He took a careful aim at the target.
正：He took careful aim at the target.
析：aim表示“瞄准”, 是不可数名词；表示“目的”或“目标”等是可数名词。如：He has only one aim in life —to be amillionaire.(他人生只有一个目标, 就是成为百万富翁)。
误：He aims becoming a doctor.
正：He aims to become a doctor.
正：He aims at becoming a doctor.
析：表示打算或计划要做某事, 可用 aim to do sth(主要用于美国英语中)或 aim at doing sth(主要用于英国英语中)，但是动词 aim 后通常不能直接跟动名词。