Help with mips program that reverses each word.?

Hello, I have a problem that has been driving me crazy. I have a program that reads a string and then reverses the string but what I need is the program to reverse each word like: ("10 is ten" becomes "01 si net"). Can anyone help? Here is what I have:
# PROGRAM:

.data # Data declaration section
a_string: .asciiz "desrever eb ot gnirts a si sihT\n"

.text # Assembly language instructions
main: la $a0,a_string #base address of string
li $v0,4 #read string
syscall

addi $a1,$zero,32 #pass lenght of string
jal stringreverse #reverse the string

stringreverse:
add $t0,$a0,$zero #starting address
add $t1,$zero,$zero #i = 0
addi $t2,$a1,-1 #j = length-1

loop:
add $t3,$t0,$t1
lb $t4,0($t3) #the lb string
add $t5,$t0,$t2
lb $t6,0($t5) #the lb string[j]
sb $t4,0($t5) #string[j] = string
sb $t6,0($t3) #string = string[j]
addi $t1,$t1,1 #i++
addi $t2,$t2,-1 #j--
#if i>=j then break - $t1 < $t2
slt $t6,$t2,$t1
beqz $t6,loop

exit:
li$v1, 4 #system call to print reversed string
la$a2, 0($a1)
syscall

li $v0, 10
syscall # Exit program

Thanks in advance for any help