Blew and blue are easily confused words.
The spell-check application of most word processing software programs would not catch a slip-up of these two words. Spell-check is looking for words that aren’t in its dictionary, and words that resemble words in its dictionary but are possibly spelled wrong. Spell-check isn’t perfect. It doesn’t know and can’t guess what word you wanted or what word you meant, it can only judge the words on the page. If you used words that are all spelled correctly, it gives you a pass anyway.
Autocorrect suggests words that start with the same letters. It’s suggesting what word you may want to save time, but quite often, its suggestions are pretty off base. They don’t help you out, but they do make you laugh.
Blew is a verb, it’s the past tense of blow. It means to drift past, like air or something in the air, at a swift rate of speed. Figuratively speaking, if someone runs past others, that person is described as blowing past. That runner isn’t actually flying, but he/she is moving at a great rate of speed compared to the other people who are standing still.
Blue is a noun. It means the color of the sky, it’s the fifth color of the rainbow. There are many shades of blue.
The following story uses both words correctly:
Blaine volunteered to help set up the cafeteria for the fall semi-formal. Unfortunately all the fun tasking–helping the hottest girls in school set up–had been taken. All that was left to do was inflating the balloons. Blaine’s temper almost blew. His original motives for volunteering had been dashed. Now this?
Inflating all those balloons by himself would take forever; it would turn his face turned red and his lips blue. Thankfully the dance committee had picked up two helium tanks to fill the balloons. They wanted them to float instead of falling to the floor. It was just going to be tedious and boring filling them all up. He would barely have time to get home and change for the event that night.