请求帮我详细解释下面的vfp代码

请求帮我详细解释下面的vfp代码
本人没有vfp基础,有段vfp程序看不懂,请求帮忙,要详细的解释哦~
public ss,t,a1,a2,b1,b2,s1,s2,s0,p1,p2,aaaa,bbbb,cccc,dddd,ffff,eeee,lzj
aaaa=1
bbbb=2
cccc=3
dddd=4
eeee=5
ffff=6
a1=thisform.text3.value/2
a2=thisform.text5.value/2
s1=val(thisform.text7.value)
b1=thisform.text4.value
b2=thisform.text6.value
s2=val(thisform.text8.value)

ss=thisform.text2.value
t=thisform.text1.value
close all
use 规格化3
appe blank
go bott
repl 板厚 with t
repl 屈服强度 with ss
use

if a2