几道八下英语题1.I need some money to buy a bike?(改为一般疑问句）2.Why don'

ang
worst
takes off
D

五一那天我女儿和我在水上乐园玩得真高兴.My daughter and I (had) (a) (good) (time) in the water park last May Day.Tina去过上海3次 Tina has been to shanghai (three) (times).

1.Do you want to____the football team?
A.take part in B.join C.join in D.take up
答案：B
join 指参加某一个团队、机构或者组织并成为其中的一员.而take part in 通常指参加活动、比赛等.
2.Could you tell me ____?
A.that it rains tomorrow B.what will the weather be like
C.how I can get to the nearest D.how can I get the nearest shop
答案：C
这里考察的是宾语从句,从句要用陈述语序.
3.The flowers in the garden need ____every day
A.watering B.to water C.waters D.be watered
答案：A
need doing 表示“某事需要被做”,本身含义被动含义.

1.
按照三角型来算
AD^2+BD^2=AB^2
AB=15; AB^2 = 225
BD = 0.6AD 因为 AD/BD = 1/0.6
AD^2 + (.6AD)^2 = 225m
AD^2 + .36AD^2 = 225m
1.36AD^2 = 225m
AD = 12.86m
DE = BC = 2m
AE = AD + DE = 14.86m
因无图,只是臆测AB,BD,AD是直角三角形,然后DE为地面到D的距离,与BC平行相等.
2.
我猜根号包含(2/a)、(a/2)和(18a)
因为我不知道根号怎么打,将以^(1/2),意为的二分之一次方来表达平方根
a(2/a)^(1/2) = (2a)^(1/2)
2(a/2)^(1/2) = (2a)^(1/2)
(18a)^(1/2) = (9)^(1/2) * (2a))^(1/2) = 3(2a)^(1/2)
和则为：5(2a)^(1/2) = 10
(2a)^(1/2) = 2 平方等号左右边,得
2a = 4, a = 2
3.
晕,请你下次必定加入括号
猜为 1/6 * x * (18x)^(1/2) - x^2 * (1/2x)^(1/2)
1/6 * x * (18x)^(1/2) = (18/36 * x^3))^(1/2) = (1/2 * x^3)^(1/2), x 进根号时变为x^2
x^2 * (1/2x)^(1/2) = (1/2 * x^4/x)^(1/2) = (1/2 * x^3)^(1/2)
两式相等,所以左减右为零.
4.
(b/2)^(1/2) - (8b)^(1/2)
(8b)^(1/2) = (16 * b/2)^(1/2) = 4(b/2)^(1/2)
(b/2)^(1/2) - 4(b/2)^(1/2) = -3(b/2)^(1/2)
5.
同3.
ab 进根号变为 (ab)^2 = a^2 * b^2
1/(ab) * (9ab^3)^(1/2) = 3(b/a)^(1/2)
3(b/a)^(1/2) - 2(b/a)^(1/2) = (b/a)^(1/2)
6.
最后这题有点变态
计算机给的答是12
可以用已知方程式(a+b)(a-b) = a^2-b^2来求答
例1/(1+√3) = (1-√3)/(1-3) = (1-√3)/(-2)
同样,后面的步骤变为
（√(2x-1) - √(2x+1))/(-2)
相加所有数,则为
（1-√625）/（-2）中间的全部都自动消掉
√625 = 25
1-25 = -24
-24/-2 = 12

1
令梯形高h
过D做DP//AC交BC延长线于P,AD//BC
所以DP=AC=8,
AC⊥BD,所以DP⊥BD
BP=10
S△DCP=S△ADC=S△ABD
所以：
S梯形=DB*DP/2=BP*h/2=（BC+AD）*h/2=DB*AC/2
h=6*8/10=4.8

Unit 1
Inviting
Dream
Afford
Pity
Prize
Make up
Called
Go on
Kinds of
Competition
Speaking
Before
Trying
In
Has also
First prize ; writing competition
Haven’t had
Used to join
Don’t have to
Unit 2
Germany
Queen
France
Tower
King
Ancient
On
Arabic
Mix
count
moved
eating
to skate
to get
haven seen
count down
is different from
has been to
so far
for example

3
EF=（AB-CD）/2.
过F作FM平行AD交AB于M,FN平行BC交AB于N.（下面简单地说一下）
AM=DF=CF=BN,AE=BE,所以,EM=EN
∠A=∠FME,∠B=∠FNE.因为,∠A+∠B=90°,所以,∠FME+∠FNE=90°.
三角形MFN为直角三角形,FE是斜边的中线,所以,EF=MN/2.
EF=（AB-AM-BN）/2=（AB-DF-CF）/2=（AB-CD）/2.