Day six

Today I have discovered that future simple is not so simple how it is called. It's used not so often. And I need to study any causes, when it is used. The future sense in English often is made by other way. For example - by present continuous: I'm working tomorrow. I can't say: I will work tomorrow. Only if I decided it just now and it was unnecessary. This thing confuses me and it's difficult for understanding. But I'll continue study English. Although it's not easy.
Difficult words:
Unnecessary
Decide
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