Starting a sentence with an "-ing" word is grammatically correct. But inexperienced writers tend to start too many sentences with "-ing" words, which makes their writing repetitive and dull or can lead to a confusing sentence structure.

For instance:

• Taking the hint, I said goodbye. Opening the door, she wished me a nice day. Looking up at the sky, I thought of asking for an umbrella, but decided it was best to leave quickly.

It can be easy to fall into the habit of repeating these sentence starts, but this will starve your writing of variety. Less than 20% of your sentences should start with "-ing" words.

You also need to be careful that your meaning is clear. "-ing" sentence starts can lead to dangling modifiers, causing confusion for readers. In our first example, the modifier "taking the hint" was near the subject "I," so the meaning was clear. But writers who start sentences with "-ing" words sometimes misplace the modifier, making it confusing:

• Considering going to the store, the empty fridge reflected in Betty's eyes.

Because of the structure of this sentence, the modifier "considering going to the store" modifies the fridge. That doesn't make any sense. The modifier should be modifying Betty:

• Considering going to the store, Betty stared into the empty fridge.

Or better yet, rewrite the sentence:

• Betty stared into the empty fridge. It was time to go to the store.

When to Use "-ing" Starts

Sometimes, an "-ing" word is a type of word called a gerund, and in these cases it's usually the right choice. A gerund is a word that comes from a verb but functions as a noun in a sentence.

Here's an example:

• Fishing is fun.

"Fishing" is a gerund—it's functioning as the subject of the sentence. In this example, it wouldn't make sense to rewrite the sentence to start without the "-ing" word, since the "-ing" word is the subject. In cases like these, using an "-ing" word at the start of your sentence is totally fine.