运行脚本出错，请好心人看看
给脚本get_perform设置权限后运行失败，不知道为什么
Administrator@AS-201210251145 ~/labw/nsp132
$ chmod +x get_perform

Administrator@AS-201210251145 ~/labw/nsp132
$ ./get_perform
./get_perform: line 10: syntax error near unexpected token `elif'
'/get_perform: line 10: `elif ["$i" -le 250 ]; then

get_perform内容为：
————————————————————————————————————————————————————————————————————

#!/bin/sh
i=1
while [ "$i" -le 300 ]; do
ns w_w.tcl $i
gawk f delay.awk rate=$i wired_wireless.tr >>delay
gawk f loss.awk rate=$i wired_wireless.tr >>loss_rate
gawk -f throughtput.awk rate=$i wired_wireless.tr >>throughtput
if ["$i" -le 225 ]; then
i=$(($i+20))
elif ["$i" -le 250 ]; then  【此处为第十行，代码中无此括号内容】
i=$(($i+5))
else
i=$(($i+2))
fi
done
exit 0

———————————————————————————————————————————————————————————————————— ns2?脚本?linux
[解决办法]

#!/bin/sh
i=1
while [ "$i" -le 300 ]; do
ns w_w.tcl $i
gawk f delay.awk rate=$i wired_wireless.tr >>delay
gawk f loss.awk rate=$i wired_wireless.tr >>loss_rate
gawk -f throughtput.awk rate=$i wired_wireless.tr >>throughtput
if [ "$i" -le 225 ]; then
i=$(($i+20))
elif [ "$i" -le 250 ]; then  【此处为第十行，代码中无此括号内容】
i=$(($i+5))
else
i=$(($i+2))
fi
done
exit 0

[解决办法]
test
[空格"$i" ]
[解决办法]
方括号的左右两边都需要空格