Thank you for your reply and correcting. But I can't understand that the following sentences (1) and (2) can use both Ving and to V. Why can't the original sentence use "writing back" instead of "to write back"?
(1)It's importand getting/to get the job done. (2)It's always dangerous talking/to talkabout politics with him.
When the it-beginning sentences with "be" verb, the following verbal could be Ving or to V ,depending on the situation, but when the sentences with the verb like "take/cost/require", the following verbal only could use to V.
I have a question about the sentence that Casi gave: Writing back took me three hours. I wonder if I can change "Writing back" to "To write back"? When "to Write back" is used? I would like to know the difference between the infinitive and the gerund when used as the subject of a sentence. Thanks a lot.
Hello, Rnaz. Thanks for joining us at English Forums. When you have a question on a new topic, it is better to start a new thread (click the 'New Post' button at the top left in any forum menu).
#1 is correct, because 'complain' is the verb. Your #2 sentence has no verb; 'complaint' is a noun.