Question about user input

Hello all,

How can i have a user input that reads like this:

echo -n "Please enter a & b:" 10 20

read a
read b

echo $a
echo $b

10
20

right now i have divided it into two echos, like

echo -n "a: "
echo -n "b: "

But how can i do it on one single line, with a blankspace between values?

/Thanks in advance.

echo "$a $b"