Pronunciation rules of vowels in English words

Pronunciation rules of vowels in English words

They begin with the letters A /: /, E /: I /, I / AI /, O / Ou /, U / U /. Generally, they begin with the definite article an instead of A. However, there are also words that begin with these letters, but the phonetic mark is wrong: ugly, where u is also a sharp sound, not / U /. Do you understand? You have to find out for yourself

Two different words have the same pronunciation for different letters
For example, the pronunciation of "e" in airport "a" and welcome is not determined by the letter in the word. As I said just now, are they the same because they have the same pronunciation? Please solve it as soon as possible. Thank you. There are others with the same pronunciation,

Phonetic pronunciation is determined, which is why it is called phonetic ~ pronunciation standard
If the pronunciation of phonetic symbols is uncertain, how do you determine the pronunciation?
Many letters or combinations of letters can pronounce the same sound, for example, a and EA can pronounce [EI] (ache, break); a letter or combination of letters can pronounce different sounds, for example, a can pronounce [EI], can pronounce [&#ə] (Abdon)

When the generatrix in a cone is fixed, what is the relationship between the radius and the height of the cone, and when the volume is the largest?
The relationship between the radius R and the height h is: L & # 178; = R & # 178; + H & # 178;, and the center angle of the circle is also unknown
What is the relationship between the radius of a cone and its height?

The volume of cone v = (1 / 3) π R & # 178; H = (1 / 3) π (L & # 178; - H & # 178;) * h
===> V=(1/3)π(L²*H-H^3)
===> V'=(1/3)π(L²-3H²)
Therefore, when l & # 178; - 3H & # 178; = 0, that is, H = (√ 3 / 3) l, the volume has a maximum
In this case, R & # 178; = L & # 178; - H & # 178; = L & # 178; - (L & # 178 / 3) = (2 / 3) l & # 178;
Then, r = (√ 6 / 3) L
So, R / h = √ 2, the volume is the largest

The playground of Guangming primary school is a rectangle with a circumference of 360 meters and a ratio of length to width of 3:2. How many square meters is the playground area?

360 △ 2 = 180m
Length 180 ± (3 + 2) X3 = 108m
Width 180-108 = 72m
Area 108x72 = 7776m2

The approximate value a / 3 + B / 7 + C / 12 obtained by rounding is approximately equal to 1.16, and the value of a, B and C can be obtained
A, B and C are three different positive integers

a=1,b=4,c=3

A 470 meter long train passes a 1030 meter long bridge in 1 minute and 30 seconds and a tunnel in 45 seconds at the same speed. How long is the tunnel

1030 + 470 = 1500m
The train speed is 1500 / 90 = 50 / 3 M / s
Tunnel length plus train length is 50 / 3 * 45 = 750m
Tunnel length = 750-470 = 280m

As shown in the figure, the rectangle ABCD has a square efgh, AF = 16 cm, HC = 13 cm, how many cm is the circumference of the rectangle ABCD

Circumference of rectangle ABCD = AF + DG + BF + BC + CG + ad = AF + DG + be + CH = 16 + 16 + 13 + 13 = 32 + 26 = 58 (CM) answer: circumference of rectangle ABCD is 58 cm

The fifth power of n is 10, so you are equal to?
How did it work out? Thank you

The second floor is wrong. It's an inverse power function, not an inverse exponential function
N is equal to the fifth power of 10
Use a scientific calculator

According to the following two mobile phone billing methods, consider the following questions. (1) for a local call time, will the two billing methods charge the same? (2) Please explain by calculation: under what circumstances is it cost-effective to use mode one telephone? Under what circumstances is it cost-effective to use mode 2 phone? In mode 1, the rent in February is 20 yuan / month, and the local call fee is 0.10 yuan / minute, and 0.20 yuan / minute

(1) When the call time is X minutes, the two kinds of charges are the same, according to the meaning of the question: 20 + 0.1 x = 0.2x, solving the equation: x = 200; answer: when the call cost is 200 minutes, the two kinds of charges are the same. (2) mode 1: 100 minutes 30 yuan 20 yuan 300 minutes 50 yuan 60 yuan, calculated by the table

As shown in the figure, in the isosceles trapezoid ABCD, ad ∥ BC, m and N are the midpoint of AD and BC respectively, and E and F are the midpoint of BM and cm respectively. (1) prove that the quadrilateral menf is a diamond; (2) if the quadrilateral menf is a square, please explore the quantitative relationship between the height of the isosceles trapezoid ABCD and the bottom BC, and prove your conclusion

(1) It is proved that: ∵ quadrilateral ABCD is isosceles trapezoid, ∵ AB = CD, ∵ a = ∵ D. ∵ m is the middle point of AD, ∵ am = DM. (2 points) ≌ ABM ≌ DCM. (1 point) ≌ BM = cm. (1 point) ∵ e, F, n are the middle points of MB, cm, BC respectively, ∵ en, FN are the median lines of △ BMC,