The best way to learn proper English is to read news report, and watch news on TV. Watching TV shows is a great way to learn casual English, slang words, understand culture reference and humor. If you have already watched these shows then you may recall the words used in the following dialogs.

and use a picture of your daughter,
you think it's TENDER.
Money Heist Season 1, Episode 4

I don't mean in my TENDER heart
it still pains me so.
Game of Thrones Season 6, Episode 5

You have a TENDER heart,
just like your mother did at your age.
Game of Thrones Season 2, Episode 10

I have a TENDER spot in my heart
for cripples, bastards and broken things.
Game of Thrones Season 1, Episode 4