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.

I figured I could cut classes
for the rest of the SEMESTER...
Breaking Bad Season 3, Episode 9

And by the... end of the SEMESTER,
by like box number five...
Breaking Bad Season 3, Episode 9