Classification of vowels is made up of the following EXCEPT（）。
The vowel is produced without (or with little) restriction during its production and is always voiced.（）
Vowels are formed mainly by the position of the tongue and, secondarily, by the shape of the lips and movement of the jaw.（）
In English， long vowels are also tense vowels because when we pronounce a long vowel such as/i：/，the larynx is in a state of tension.
The most powerful signal of stress is a change of pitch on the vowel.（）
_ is NOT included in the factors used in analyzing vowels.
An infant can recognize a lot of vowels by the time he or she is a year old.
The English pure vowels can be classified according to the height of the raised part of the tongue.
The number of the vowels are equal in English and Mongolian.
The vowel sound in the word ‘hot’ is [ɑ].
In Paras. 6—13, three methods of animal protection are mentioned,which of the following is not correct?
There are three types of resume mentioned in the lesson, such as_________.
Which group of the words has the same vowel sound?
Generally, the light /l/comes before the vowel or diphthong in a syllable, but what about the dark /l/?_____________ the vowel or diphtong in a syllable. (After; Before)
How many ways can be used to signal the stressed syllables?There are three ways to signal the stressed syllables: lengthen it, say it louder with clear vowel and raise the pitch.
Why does the author mention the psychological condition of the driver in Paragraph Three？ 查看材料
Why does the author mention "the Louisiana Purchase"？
Vowel sounds are classified by a number of factors: the position of the tongue in the
A ______word is often on a higher pitch and it has a longer duration, i.e.the vowel appe
[＋sonorant] is only shared by all the vowels.（)
Bilabial semi-vowel refers to the sound__________．
The sudden vowel shift in the history of English helped to shape__ English（）
Vowels which trigger [r]-insertion never trigger [j]-insertion or [w]-insertion. Each glide has its own domain, although the domains exempt short stressed vowels /e, ？, ？, ？, ？/, which never occur word-finally in English.
One important feature that marks the difference between vowels and constants is that
