IELTS Grammar: subject + verb

Question: Which of the following is a correct sentence?

1. Learning a foreign language.
2. Firstly, learning a foreign language in order to improve your career prospects.
3. For example, learning a foreign language by living in a country where that language is spoken, and communicating with native speakers on a daily basis.

Answer: None of these are correct sentences. None of them has a main verb.

To make a sentence, you need a subject (noun/noun phrase) and a verb:

1. I am learning a foreign language. OR, Learning a foreign language is useful.
2. Firstly, many people learn a foreign language in order to improve their career prospects.
3. For example, some people learn a foreign language by living in a country where that language is spoken and communicating with native speakers on a daily basis.

Some students really need to work on writing correct "subject + verb" sentences. Missing the verb in a sentence is a serious mistake that will definitely affect your score.