English: using “it” as a subject

Tutoring English, common constructions can cause review. The tutor mentions using “it” as a subject.

Scenario 1

Speaker A: What’s the weather?
Speaker B: It’s raining.

Scenario 2

Speaker A: How can you tell someone is lying?
Speaker B: It’s easy to tell.

In Scenario 1 above, “It” may refer to the weather itself: The weather is raining. Yet, you seldom hear The weather is raining.

In Scenario 2, “It” may refer to the fact that someone is lying: The fact that someone is lying is easy to tell.

Such use of “it” can be referred to as a “dummy” subject: the subject itself isn’t thought of, yet the sentence’s meaning is clear.

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