The -ing form is used when the word is the subject of a sentence or clause:
Swimming is good exercise
Doctors say that smoking is bad for you
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The -ing form is used after a preposition

I look forward to meeting you
They left without saying "Goodbye
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The -ing form is used after certain verbs
- avoid, dislike, enjoy, finish, give up, mind/not mind, practise

I dislike getting up early
Would you mind opening the window
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We use the Present Continuous Tense to talk about activities happening now
The kids are watching TV
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We can also use the Present Continuous Tense to talk about activities happening around now, and not necessarily this very moment


Sally is studying really hard for her exams this week
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