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.

The earliest ESTIMATE
of the singularity.
The Big Bang Theory Season 4, Episode 2

You're monitoring the telescope
for 12 hours, and by my ESTIMATE...
The Big Bang Theory Season 4, Episode 9

I suppose it wouldn't hurt
to get an ESTIMATE.
The Big Bang Theory Season 2, Episode 21

giving me an ESTIMATE
of your annual cash flow here.
Breaking Bad Season 4, Episode 2