《吕氏春秋·上农》在描述农耕之利时不无夸张地说：一个农夫耕种肥沃的土地可以养活九口人，耕种一般的土地也能养活五口人。战国时期农业收益的增加（    ）

    I've come to the conclusion that I'm rubbish at saying “NO”.For example, last Sunday I was sitting at my desk alone，totally 1 in my own business, when a colleague (同事) of mine phoned and asked me to get involved in 2 with her. I found myself getting all caught up in her enthusiasm and didn't want to 3 her.So I said “Sure，why not?” and before the call had 4, I found myself agreeing without giving any 5 whether it was worth doing.

    We are both window-shoppers and 6 a whole day in the street. Actually, I hardly have any time to spare because I am very busy 7 my normal job—I've also got a book to write，a business to 8 and a family to look after. And then there are my other projects to 9— my voluntary work and a couple of other interesting investments(投资) that I want to 10. I'm going to have to be more ruthless(无情的)and not just agree to 11 people ask me to get involved in. In other words，I'm going to have to get 12 at saying “NO”.Usually I hate saying “NO”，because having to disappoint someone usually 13 me. Now I realize 14 I haven't learned to say “NO”. I've been feeling very 15.

    We had better do what we think is right and what we are 16 to do.Sometimes it does not seem that bad to 17 others.If I focus on the things I 18 want to be involved in，I'11 reach a much higher standard and do it quite 19. I'1l be enthusiastic and motivated(有积极性)and do something that is good for everyone and everyone will be happy.It'11 be a win-win 20. What's not good about that? So sometimes, we have to say “NO”.

小敏编写了一个VB程序，用来求一个偶数(6到100之间)可能存在多少这样的素数对（注： A+B与B+A认为是相同素数对，不重复统计），并把这些结果输出到一个列表框中，通过逻辑推理，小敏发现这些素数对都是奇数，所以她只需要验证奇数的素数对即可。运行界面如图所示，程序代码如下。但加框处代码有错，请改正。

Dim IsPrime(100) As Boolean  '用来存储是否素数，True为素数，False为非素数

Private Sub Command1_Click()

    Dim x As Integer, y As Integer, i As Integer, num As Integer

Call Init  '调用Init函数

    x = Val(Text1.Text)

y = x \ 2

num = 0

For i = 3 To y Step 2

                 '①

num = num + 1

            List1.AddItem Str(x) + "=" + Str(i) + "+" + Str(x - i)

        End If

    Next i

    Label2.Caption = "偶数" + Str(x) + "共有" + Str(num) + "个素数对。"

End Sub

Sub Init() '初始化IsPrime数组的值

    Dim i As Integer, j As Integer, x As Integer

    For i = 3 To 100 Step 2

        x = Int(Sqr(i))

                            '②

            If i Mod j = 0 Then Exit For

        Next j

        If j > x Then IsPrime(i) = True Else IsPrime(i) = False

    Next i

End Sub

①____ ②____