a 在开音节中 [ei] name plane Jane baby cake
在闭音节中 [æ] bag dad hat map black back
a在[w]音后面 [D] want what watch wash quality
a在f n sk ph sp ss st th前 [α:] after plant graph ask grasp glass fast father
a [ə] China another woman breakfast
a[ε] care dare hare
a[ə:]again