1. The correct answer is "Whose". "Whose" is used to ask about possession or ownership. In this case, the question is asking who the bà (object) belongs to.

2. The correct answer is "My boyfriend loses". "Short-tempered" means easily angered or irritable. However, the phrase "loses temper" is more commonly used to describe someone who gets angry easily.

3. The correct answer is "No matter". The phrase "as long as" is used to indicate a condition or requirement that must be met. In this case, it means that you can use "it" for any length of time without it getting worn out.

4. The correct answer is not provided in the options. The sentence states that the train couldn't run because of the snow. This means that the snow prevented the train from operating or moving.