Gun for (someone)
To look hard for a chance to harm or defeat someone.My supervisor has been gunning for me for a long time and I do not know why.
Gum up
To cause something not to work, to make something go wrong.The computer printer became gummed up as I was trying to print my resume.
Gulp for air
To desperately try to get some air or a breath.The man began gulping for air after he fell into the lake.
Guest of honor
The special person for whom a party or ceremony is held.My father was the guest of honor at the company banquet.
Guard one’s tongue
To be careful of what one says.I have to guard my tongue when I am speaking with my friend's parents.
Guard against (someone or something)
To take care to avoid someone or something.When we go to the beach we must guard against the hot sun.
Grunt work
Hard and thankless work.I am often forced to do the grunt work at my company.
Grow to do/like (something)
To gradually begin to do something or like someone or something.I am growing to like the people who live next door to me.
Grow out of (something)
To abandon something as one matures or becomes older.The little boy is beginning to grow out of his baby chair.
Grow on (someone)
To become acceptable to someone or liked by someone.At first, I did not like the strange music but now it is beginning to grow on me.