Timing limiter for execution of commands in Bash/Shell Script

Question

I have a shell script which looks like this:

echo firstOutput
read -s
command0
command1a
command1b
command1c
echo secondOutput
command2

command1a, command1b, command1c are individual commands but they can be executed in arbitrary order and are a group in the sense of the following explanation.

I now want to improve it so the script continues even if one command gets stuck. command0 needs to be executed first and it got 8 seconds to operate. If it doesn't make it within 8 seconds, the script shall continue to command1[a-c] which together have 5 seconds to operate. If they don't terminate within the given 5 seconds, command2 shall be called. Just in case this matters: command2 is the last command of this script.

Edit: To clarify: I know how to make a script which executes the commands in the maximum time allowed. However, these are timeouts and I want the script to run through as fast as possible. The entire script usually runs through in a fraction of a second after enter is pressed (see line read -s).

Answer 1

echo firstOutput
read -s

command0 &
sleep 8

command1a &
command1b &
command1c &
sleep 5

echo secondOutput
command2

Answer 2

The timeout command does exactly what you seem to want. See man timeout:

NAME
   timeout - run a command with a time limit

SYNOPSIS
   timeout [OPTION] DURATION COMMAND [ARG]...
   timeout [OPTION]

DESCRIPTION
   Start COMMAND, and kill it if still running after DURATION.