In the USA, different people celebrate Christmas in really different ways. Some people celebrate it because it is a really important Christian holiday -- the day to remember when Jesus was born.
Many non-religious and religious-but-not-Christian people in the USA celebrate Christmas as a great time to celebrate love, friendship, and family -- they shop, party, spend time with family, go to parties with friends, send cards, and give presents.
The most important thing you can do to improve English is use English -- talk to people, read, listen, and write English.
I like to teach Grammar because if you use it well, it's an excellent short cut. If you catch the rule with the grammar pattern, you can immediately understand how to say 10,000 things correctly. Also, advanced classes usually use grammar rules, and understanding basic grammar ideas and how to use grammar with lots of examples to learn a language makes those classes easy rather than incomprehensible.
Try to remember grammar rules, but don't get mad when they don't work 100%.
Make tons of your own examples from the rule, and ask a native speaker if they are correct.
Repeat correct useful phrases a LOT
Can you find any grammar mistakes in this grammar song?
Some people in our class got an excellent grammar education before this class. Some never had a chance to learn grammar before. Here are links for some of grammar you should master before going to high intermediate. If you want grammar practice, try these links.
חנוכה commemorates the re-dedication of the holy temple in Jerusalem. In the US, Jewish people get together, light candles, and give gifts for eight days. In the USA, Hannukah is a big holiday, partly because it gets commercialized in a similar way to Christmas.